Chapter 6. Making Users Happy

Table of Contents

Introduction
Assignment Tasks
Dissection and Discussion
Technical Issues
Political Issues
Installation Check-List
Samba Server Implementation
OpenLDAP Server Configuration
PAM and NSS Client Configuration
Samba-3 PDC Configuration
Install and Configure Idealx SMB-LDAP Scripts
LDAP Initialization and Creation of User and Group Accounts
Printer Configuration
Samba-3 BDC Configuration
Miscellaneous Server Preparation Tasks
Configuring Directory Share Point Roots
Configuring Profile Directories
Preparation of Logon Scripts
Windows Client Configuration
Configuration of Default Profile with Folder Redirection
Configuration of MS Outlook to Relocate PST File
Configure Delete Cached Profiles on Logout
Uploading Printer Drivers to Samba Servers
Software Installation
Roll-out Image Creation
Key Points Learned
Questions and Answers

It has been said, “A day that is without troubles is not fulfilling. Rather, give me a day of troubles well handled so that I can be content with my achievements.

In the world of computer networks, problems are as varied as the people who create them or experience them. The design of the network implemented in the last chapter may create problems for some network users. The following lists some of the problems that may occur:

Users experiencing difficulty logging onto the network

When a Windows client logs onto the network, many data packets are exchanged between the client and the server that is providing the network logon services. Each request between the client and the server must complete within a specific time limit. This is one of the primary factors that govern the installation of multiple domain controllers (usually called secondary or backup controllers). As a rough rule, there should be one such backup controller for every 30 to 150 clients. The actual limits are determined by network operational characteristics.

If the domain controller provides only network logon services and all file and print activity is handled by Domain Member servers, one Domain Controller per 150 clients on a single network segment may suffice. In any case, it is highly recommended to have a minimum of one Domain Controller (PDC or BDC) per network segment. It is better to have at least one BDC on the network segment that has a PDC. If the Domain Controller is also used as a file and print server, the number of clients it can service reliably is reduced and a common rule is not to exceed 30 machines (Windows workstations plus Domain Member servers) per Domain Controller.

Slow logons and log-offs

Slow logons and log-offs may be caused by many factors that include:

  • Excessive delays in the resolution of a NetBIOS name to its IP address. This may be observed when an overloaded domain controller is also the WINS server. Another cause may be the failure to use a WINS server (this assumes that there is a single network segment).

  • Network traffic collisions due to overloading of the network segment one short-term workaround to this may be to replace network HUBs with Ether-switches.

  • Defective networking hardware. Over the past few years, we have seen on the Samba mailing list a significant increase in the number of problems that were traced to a defective network interface controller, a defective HUB or Etherswitch, or defective cabling. In most cases, it was the erratic nature of the problem that ultimately pointed to the cause of the problem.

  • Excessively large roaming profiles. This type of problem is typically the result of poor user eduction, as well as poor network management. It can be avoided by users not storing huge quantities of email in MS Outlook PST files, as well as by not storing files on the desktop. These are old bad habits that require much discipline and vigilance on the part of network management.

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You should verify that the Windows XP WebClient service is not running. The use of the WebClient service has been implicated in many Windows networking related problems.

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Loss of access to network drives and printer resources

Loss of access to network resources during client operation may be caused by a number of factors including:

  • Network overload (typically indicated by a high network collision rate)

  • Server overload

  • Timeout causing the client to close a connection that is in use, but has been latent (no traffic) for some time (5 minutes or more)

  • Defective networking hardware

No matter what the cause, a sudden operational loss of access to network resources can result in BSOD (blue screen of death) situations that necessitate rebooting of the client workstation. In the case of a mild problem, retrying to access the network drive of printer may restore operations, but in any case this is a serious problem as it may lead to the next problem, data corruption.

Potential data corruption

Data corruption is one of the most serious problems. It leads to uncertainty, anger, and frustration, and generally precipitates immediate corrective demands. Management response to this type of problem may be rational, as well as highly irrational. There have been cases where management has fired network staff for permitting this situation to occur without immediate correction. There have been situations where perfectly functional hardware was thrown out and replaced, only to find the problem caused by a low-cost network hardware item. There have been cases where server operating systems were replaced, or where Samba was updated, only to later isolate the problem due to defective client software.

In this chapter, you can work through a number of measures that significantly arm you to anticipate and to combat network performance issues. You can work through complex and thorny methods to improve the reliability of your network environment, but be warned that all such steps demand the price of complexity.

Introduction

Mr. Bob Jordan just opened an email from Christine that reads:

Bob,

 

A few months ago we sat down to design the network. We discussed the challenges ahead and we all agreed to compromise our design to keep it simple. We knew there would be problems, but anticipated that we would have some time to resolve any issues that might be encountered.

As you now know we started off on the wrong foot. We have a lot of unhappy users. One of them resigned yesterday afternoon because she was under duress to complete some critical projects. She suffered a blue screen of death situation just as she was finishing four hours of intensive work, all of which was lost. She has a unique requirement that involves storing large files on her desktop. Mary's desktop profile is nearly 1 Gigabyte in size. As a result of her desktop configuration, it takes her nearly 15 minutes just to log onto her workstation. But that is not enough. Because all network logon traffic passes over the network links between our buildings, logging on may take three or four attempts due to blue screen problems associated with network timeouts.

A few of us worked to help her out of trouble. We convinced her to stay and promised to fully resolve the difficulties she is facing. We have no choice. We must implement LDAP and set hard limits on what our users can do with their desktops. If we do not do this, we face staff losses that can surely do harm to our growth, as well as to staff morale. I am sure we can better deal with the consequences of what we know we must do than we can with the unrest we have now.

Stan and I have discussed the current situation. We are resolved to help our users and protect the well being of Abmas. Please acknowledge this advice with consent to proceed as required to regain control of our vital IT operations.

 
--Christine 

Every compromise has consequences. Having a large routed (i.e., multi-segment) network with only a single domain controller is a poor design that has obvious operational effects that may frustrate users. Here is Bob's reply:

 

Christine, Your diligence and attention to detail are much valued. Stan and I fully support your proposals to resolve the issues. I am confident that your plans fully realized will significantly boost staff morale. Please go ahead with your plans. If you have any problems, please let me know. Please let Stan know what the estimated cost will be so I can approve the expense. Do not wait for approval; I appreciate the urgency.

 
--Bob 

Assignment Tasks

The priority of assigned tasks in this chapter is:

  1. Implement Backup Domain Controllers (BDCs) in each building. This involves a change from use of a tdbsam backend that was used in the previous chapter, to use an LDAP-based backend.

    You can implement a single central LDAP server for this purpose.

  2. Rectify the problem of excessive logon times. This involves redirection of folders to network shares as well as modification of all user desktops to exclude the redirected folders from being loaded at login time. You can also create a new default profile that can be used for all new users.

You configure a new MS Windows XP Professional Workstation disk image that you roll out to all desktop users. The instructions you have created are followed on a staging machine from which all changes can be carefully tested before inflicting them on your network users.

This is the last network example in which specific mention of printing is made. The example again makes use of the CUPS printing system.

Dissection and Discussion

The implementation of Samba BDCs necessitates the installation and configuration of LDAP. For this site, you use OpenLDAP, the open source software LDAP server platform. Commercial LDAP servers in current use with Samba-3 include:

  • Novell eDirectory. eDirectory is being successfully used by some sites. Information on how to use eDirectory can be obtained from the Samba mailing lists or from Novell.

  • IBM Tivoli Directory Server, can be used to provide the Samba LDAP backend. Example schema files are provided in the Samba source code tarball under the directory ~samba/example/LDAP.

  • Sun ONE Identity Server. This product suite provides an LDAP server that can be used for Samba. Example schema files are provided in the Samba source code tarball under the directory ~samba/example/LDAP.

A word of caution is fully in order. OpenLDAP is purely an LDAP server and unlike commercial offerings, it requires that you manually edit the server configuration files and manually initialize the LDAP directory database. OpenLDAP itself has only command line tools to help you to get OpenLDAP and Samba-3 running as required, albeit with some learning curve challenges.

For most sites, the deployment of Microsoft Active Directory from the shrink-wrapped installation is quite adequate. If you are migrating from Microsoft Active Directory, be warned that OpenLDAP does not include GUI-based directory management tools. Even a simple task such as adding users to the OpenLDAP database requires an understanding of what you are doing, why you are doing it, and the tools that you must use.

When installed and configured, an OpenLDAP Identity Management backend for Samba functions well. High availability operation may be obtained through directory replication/synchronization and master/slave server configurations. OpenLDAP is a mature platform to host the organizational directory infrastructure that can include all UNIX accounts, directories for electronic mail, and much more. The price paid through learning how to design an LDAP directory schema in implementation and configuration of management tools is well rewarded by performance and flexibility, and the freedom to manage directory contents with greater ability to back up, restore, and modify the directory than is generally possible with Microsoft Active Directory.

A comparison of OpenLDAP with Microsoft Active Directory does not do justice to either. OpenLDAP is an LDAP directory tool-set. Microsoft Active Directory Server is an implementation of an LDAP server that is largely pre-configured for a specific task orientation. It comes with a set of administrative tools that is entirely customized for the purpose of running MS Windows applications that include file and print services, Microsoft Exchange server, Microsoft SQL server, and more. The complexity of OpenLDAP is highly valued by the UNIX administrator who wants to built a custom directory solution. Microsoft Active Directory is a generic LDAP server that has been pre-configured for a specific task. Microsoft provides an application called MS ADAM that provides more-generic LDAP services, yet it does not have the vanilla-like services of OpenLDAP.

You may wish to consider outsourcing the development of your OpenLDAP directory to an expert, particularly if you find the challenge of learning about LDAP directories, schemas, configuration, and management tools, and the creation of shell and Perl scripts a bit challenging. OpenLDAP can be easily customized, though it includes many ready-to-use schemas. Samba-3 provides an OpenLDAP schema file that is required for use as a passdb backend.

For those who are willing to brave the process of installing and configuring LDAP and Samba-3 interoperability, there are a few nice Web-based tools that may help you to manage your users and groups more effectively. The Web-based tools you might like to consider include: The LDAP Account Manager (LAM), as well as the Webmin-based Idealx CGI tools.

Some additional LDAP tools should be mentioned. Every so often a Samba user reports using one of these so it may be useful to include passing reference to them. The first is GQ, a GTK-ased LDAP browser; LDAP Browser/Editor, JXplorer (by Computer Associates), and the last is called phpLDAPadmin.

Note

The following prescriptive guidance is not an LDAP tutorial. The LDAP implementation expressly lacks security. No form of secure LDAP communications is attempted. The LDAP configuration information provided is considered to consist of the barest essentials only. You are strongly encouraged to learn more about LDAP before attempting to deploy it in a business-critical environment.

Information to help you get started with OpenLDAP is available from the OpenLDAP Web Site. Many people have found the book LDAP System Administration, written by Jerry Carter, quite useful.

Mary's problems are due to two factors. First, the absence of a domain controller on the local network is the main cause of the errors that result in blue screen crashes. Second, Mary has a large profile that must be loaded over the wide-area network connection. This addition of BDCs on each network segment significantly improves overall network performance for most users, but this is not enough. You must gain control over user desktops, and this must be done in a way that wins their support and does not cause further loss of staff morale. The following procedures solve this problem.

There is also an opportunity to implement smart printing features. You add this to the Samba configuration so that future printer changes can be managed without need to change desktop configurations.

You add the ability to automatically download new printer drivers, even if they are not installed in the default desktop profile. Only one example of printing configuration is given. It is assumed that you can extrapolate the principles and use this to install all printers that may be needed.

Technical Issues

The solution provided is a minimal approach to getting OpenLDAP running as an identity management directory server for UNIX system accounts as well as for Samba. From the OpenLDAP perspective, UNIX system accounts are stored Posix schema extensions. Samba provides its own schema to permit storage of account attributes Samba needs. Samba-3 can use the LDAP backend to store:

  • Windows Networking User Accounts

  • Windows NT Group Accounts

  • Mapping Information between UNIX Groups and Windows NT Groups

  • ID Mappings for SIDs to UIDs (also for foreign Domain SIDs)

The use of LDAP with Samba-3 makes it necessary to store UNIX accounts as well as Windows Networking accounts in the LDAP backend. This implies the need to use the PADL LDAP tools. The resolution of the UNIX group name to its GID must be enabled from either the /etc/group or from the LDAP backend. This requires the use of the PADL nss_ldap toolset that integrates with the name service switcher (NSS). The same requirements exist for resolution of the UNIX username to the UID. The relationships are demonstrated in ???.

Figure 6.1. The Interaction of LDAP, UNIX Posix Accounts and Samba Accounts

The Interaction of LDAP, UNIX Posix Accounts and Samba Accounts

You configure OpenLDAP so that it is operational. Before deploying the OpenLDAP, you really ought to learn how to configure secure communications over LDAP so that sites security is not at risk. This is not covered in the following guidance.

When OpenLDAP has been made operative, you configure the Primary Domain Controller (PDC) called MASSIVE. You initialize the Samba secrets.tdb file. Then you create the LDAP Interchange Format (LDIF) file from which the LDAP database can be initialized. You need to decide how best to create user and group accounts. A few hints are, of course, provided. You can also find on the enclosed CD-ROM, in the Chap06 directory, a few tools that help to manage user and group configuration.

In order to effect folder redirection and to add robustness to the implementation, create a network Default Profile. All network users workstations are configured to use the new profile. Roaming profiles will automatically be deleted from the workstation when the user logs off.

The profile is configured so that users cannot change the appearance of their desktop. This is known as a mandatory profile. You make certain that users are able to use their computers efficiently.

A network logon script is used to deliver flexible but consistent network drive connections.

Roaming Profile Background

As XP roaming profiles grow, so does the amount of time it takes to log in and out.

An XP Roaming Profile consists of the HKEY_CURRENT_USER hive file NTUSER.DAT and a number of folders (My Documents, Application Data, Desktop, Start Menu, Templates, NetHood, Favorites, and so on). When a user logs onto the network with the default configuration of MS Windows NT/200x/XPP, all this data is copied to the local machine. By default it is copied to the local machine, under the C:\Documents and Settings\%USERNAME% directory. While the user is logged in, any changes made to any of these folders or to the HKEY_CURRENT_USER branch of the registry are made to the local copy of the profile. At logout the profile data is copied back to the server. This behavior can be changed through appropriate registry changes and/or through changes to the Default User profile. In the latter case, it updates the registry with the values that are set in the profile NTUSER.DAT file.

The first challenge is to reduce the amount of data that must be transferred to and from the profile server as roaming profiles are processed. This includes removing all the shortcuts in the Recent directory, making sure the cache used by the web browser is not being dumped into the Application Data folder, removing the Java plug-in's cache (the .jpi_cache directory in the profile), as well as training the user to not place large files on the Desktop and to use his mapped home directory for saving documents instead of the My Documents folder.

Using a folder other than My Documents is a nuisance for some users since many applications use it by default.

The secret to rapid loading of roaming profiles is to prevent unnecessary data from being copied back and forth, without losing any functionality. This is not difficult; it can be done by making changes to the Local Group Policy on each client as well as changing some paths in each user's NTUSER.DAT hive.

Every user profile has their own NTUSER.DAT file. This means you need to edit every user's profile, unless a better method can be followed. Fortunately, with the right preparations, this is not difficult. It is possible to remove the NTUSER.DAT file from each user's profile. Then just create a Network Default Profile. Of course, it is necessary to copy all files from redirected folders to the network share to which they are redirected.

The Local Group Policy

Without an Active Directory PDC, you cannot take full advantage of Group Policy Objects. However, you can still make changes to the Local Group Policy by using the Group Policy editor (gpedit.msc).

The Exclude directories in roaming profile settings can be found under User Configuration->Administrative Templates->System->User Profiles. By default this setting contains: “Local Settings;Temporary Internet Files;History;Temp”.

Simply add the folders you do not wish to be copied back and forth to this semi-colon separated list. Note that this change must be made on all clients that are using roaming profiles.

Profile Changes

There are two changes that should be done to each user's profile. Move each of the directories that you have excluded from being copied back and forth out of the usual profile path. Modify each user's NTUSER.DAT file to point to the new paths that are shared over the network, instead of the default path (C:\Documents and Settings\%USERNAME%).

The above modifies existing user profiles. So that newly created profiles have these settings, you will need to modify the NTUSER.DAT in the C:\Documents and Settings\Default User folder on each client machine, changing the same registry keys. You could do this by copying NTUSER.DAT to a Linux box and using regedt32. The basic method is described under ???.

Using a Network Default User Profile

If you are using Samba as your PDC, you should create a file-share called NETLOGON and within that create a directory called Default User, which is a copy of the desired default user configuration (including a copy of NTUSER.DAT. If this share exists and the Default User folder exists, the first login from a new account pulls its configuration from it. See also: the Real Men Don't Click Web site.

Installation of Printer Driver Auto-Download

The subject of printing is quite topical. Printing problems run second place to name resolution issues today. So far in this book, you have experienced only what is generally known as “dumb” printing. Dumb printing is the arrangement where all drivers are manually installed on each client and the printing subsystems perform no filtering or intelligent processing. Dumb printing is easily understood. It usually works without many problems, but it has its limitations also. Dumb printing is better known as Raw Print Through printing.

Samba permits the configuration of Smart printing using the Microsoft Windows point-and-click (also called drag-and-drop) printing. What this provides is essentially the ability to print to any printer. If the local client does not yet have a driver installed, the driver is automatically downloaded from the Samba server and installed on the client. Drag-and-drop printing is neat; it means the user never needs to fuss with driver installation, and that is a Good Thing™, isn't it?

There is a further layer of print job processing that is known as Intelligent printing that automatically senses the file format of data submitted for printing and then invokes a suitable print filter to convert the incoming data stream into a format suited to the printer to which the job is dispatched.

The CUPS printing subsystem is capable of intelligent printing. It has the capacity to detect the data format and apply a print filter. This means that it is feasible to install on all Windows clients a single printer driver for use with all printers that are routed through CUPS. The most sensible driver to use is one for a Postscript printer. Fortunately, Easy Software Products, the authors of CUPS have released a Postscript printing driver for Windows. It can be installed into the Samba printing backend so that it automatically downloads to the client when needed.

This means that so long as there is a CUPS driver for the printer, all printing from Windows software can use Postscript, no matter what the actual printer language for the physical device is. It also means that the administrator can swap out a printer with a totally different type of device without ever needing to change a client workstation driver.

This book is about Samba-3, so you can confine the printing style to just the smart style of installation. Those interested in further information regarding intelligent printing should review documentation on the Easy Software Products Web site.

Political Issues

MS Windows network users are generally very sensitive to limits that may be imposed when confronted with locked-down workstation configurations. The challenge you face must be promoted as a choice between reliable and fast network operation, and a constant flux of problems that result in user irritation.

Installation Check-List

You are starting a complex project. Even though you have gone through the installation of a complex network in chapter 5, this network is a bigger challenge because of the large number of complex applications that must be configured before the first few steps can be validated. Take stock of what you are about to undertake, prepare yourself, and frequently review the steps ahead while making at least a mental note of what has already been completed. The following task list may help you to keep track of the task items that are covered:

  • Samba-3 PDC Server Configuration

    1. DHCP and DNS Servers

    2. OpenLDAP Server

    3. PAM and NSS Client Tools

    4. Samba-3 PDC

    5. Idealx SMB-LDAP Scripts

    6. LDAP Initialization

    7. Create User and Group Accounts

    8. Printers

    9. Share Point Directory Roots

    10. Profile Directories

  • Samba-3 BDC Server Configuration

    1. DHCP and DNS Servers

    2. PAM and NSS Client Tools

    3. Printers

    4. Share Point Directory Roots

    5. Profiles Directories

  • Samba-3 BDC Server Configuration

  • Windows XP Client Configuration

    1. Default Profile Folder Redirection

    2. MS Outlook PST File Relocation

    3. Delete Roaming Profile on Logout

    4. Upload Printer Drivers to Samba Servers

    5. Install Software

    6. Creation of Roll-out Images

Samba Server Implementation

The network design shown in ??? is not comprehensive. It is assumed that you will install additional file servers, and possibly additional BDCs.

Figure 6.2. Network Topology 500 User Network Using ldapsam passdb backend.

Network Topology 500 User Network Using ldapsam passdb backend.

All configuration files and locations are shown for SUSE Linux 9.0. The file locations for Red Hat Linux are similar. You may need to adjust the locations for your particular Linux system distribution/implementation.

The steps in the process involve changes from the network configuration shown in ???. Before implementing the following steps, you must have completed the network implementation shown in that chapter. If you are starting with newly installed Linux servers, you must complete the steps shown in ??? before commencing at ???:

OpenLDAP Server Configuration

Confirm that the packages shown in ??? are installed on your system.

Table 6.1. Required OpenLDAP Linux Packages

SUSE Linux 8.xSUSE Linux 9Red Hat Linux 9
nss_ldapnss_ldapnss_ldap
pam_ldappam_ldappam_ldap
openldap2openldap2openldap
openldap2-clientopenldap2-client 
 openldap2-back-perl 
 openldap2-back-monitor 
 openldap2-back-ldap 
 openldap2-back-meta 

Samba-3 and OpenLDAP will have a degree of inter-dependence that is unavoidable. The method for boot-strapping the LDAP and Samba-3 configuration is relatively straight forward. If you follow these guidelines, the resulting system should work fine.

  1. Install the file shown in ??? in the directory /etc/openldap.

  2. Remove all files from the directory /var/lib/ldap, making certain that the directory exists with permissions:

    root#  ls -al /var/lib | grep ldap
    drwx------   2 ldap    ldap       48 Dec 15 22:11 ldap
    

    This may require you to add a user and a group account for LDAP if they do not exist.

Example 6.1. LDAP Master Configuration File /etc/openldap/slapd.conf

include		/etc/openldap/schema/core.schema
include		/etc/openldap/schema/cosine.schema
include		/etc/openldap/schema/inetorgperson.schema
include		/etc/openldap/schema/nis.schema
include		/etc/openldap/schema/samba.schema

pidfile		/var/run/slapd/slapd.pid
argsfile	/var/run/slapd/slapd.args

database	ldbm
suffix		"dc=abmas,dc=biz"
rootdn		"cn=Manager,dc=abmas,dc=biz"

# rootpw = not24get
rootpw          {SSHA}86kTavd9Dw3FAz6qzWTrCOKX/c0Qe+UV

directory	/var/lib/ldap

# Indices to maintain
index objectClass           eq
index cn                    pres,sub,eq
index sn                    pres,sub,eq
index uid                   pres,sub,eq
index displayName           pres,sub,eq
index uidNumber             eq
index gidNumber             eq
index memberUID             eq
index sambaSID              eq
index sambaPrimaryGroupSID  eq
index sambaDomainName       eq
index default               sub

PAM and NSS Client Configuration

The steps that follow involve configuration of LDAP, Name Service Switch (NSS) LDAP-based resolution of users and groups. Also, so that LDAP-based accounts can log onto the system, the steps ahead configure the Pluggable Authentication Modules (PAM) to permit LDAP-based authentication.

Since you have chosen to put UNIX user and group accounts into the LDAP database, it is likely that you may want to use them for UNIX system (Linux) local machine logons. This necessitates correct configuration of the Pluggable Authentication Modules (PAM). The pam_ldap open source package provides the PAM modules that most people would use. On SUSE Linux systems, the pam_unix2.so module also has the ability to redirect authentication requests through LDAP.

You have chosen to configure these services by directly editing the system files but, of course, you know that this configuration can be done using system tools provided by the Linux system vendor. SUSE Linux has a facility in YaST (the system admin tool) through yast->system->ldap-client that permits configuration of SUSE Linux as an LDAP client. Red Hat Linux provides the authconfig tool for this.

Example 6.2. Configuration File for NSS LDAP Support /etc/ldap.conf

SIZELIMIT	200
TIMELIMIT	15
DEREF		never

host 127.0.0.1
base dc=abmas,dc=biz
binddn cn=Manager,dc=abmas,dc=biz
bindpw not24get

pam_password exop

nss_base_passwd	ou=People,dc=abmas,dc=biz?one
nss_base_shadow	ou=People,dc=abmas,dc=biz?one
nss_base_group  ou=Groups,dc=abmas,dc=biz?one

Example 6.3. Configuration File for NSS LDAP Clients Support /etc/ldap.conf

SIZELIMIT	200
TIMELIMIT	15
DEREF		never

host  172.16.0.1
base dc=abmas,dc=biz
binddn cn=Manager,dc=abmas,dc=biz
bindpw not24get

pam_password exop

nss_base_passwd ou=People,dc=abmas,dc=biz?one
nss_base_shadow ou=People,dc=abmas,dc=biz?one
nss_base_group  ou=Groups,dc=abmas,dc=biz?one
  1. Execute the following command to find where the nss_ldap module expects to find its control file:

    root#  strings /lib/libnss_ldap.so.2 | grep conf
    

    The preferred and usual location is /etc/ldap.conf.

  2. On the server MASSIVE, install the file shown in ??? into the path that was obtained from the step above. On the servers called BLDG1 and BLDG2, install the file shown in ??? into the path that was obtained from the step above.

  3. Edit the NSS control file (/etc/nsswitch.conf) so that the lines that control user and group resolution will obtain information from the normal system files as well as from ldap as follows:

    passwd: files ldap
    shadow: files ldap
    group:  files ldap
    hosts:  files dns wins
    

    Later, when the LDAP database has been initialized and user and group accounts have been added, you can validate resolution of the LDAP resolver process. The inclusion of WINS-based hostname resolution is deliberate so that all MS Windows client hostnames can be resolved to their IP addresses, whether or not they are DHCP clients.

  4. For PAM LDAP configuration on this SUSE Linux 9.0 system, the simplest solution is to edit the following files in the /etc/pam.d directory: login, password, samba, sshd. In each file, locate every entry that has the pam_unix2.so entry and add to the line the entry use_ldap as shown for the login module in this example:

    #%PAM-1.0
    auth      requisite  pam_unix2.so   nullok use_ldap #set_secrpc
    auth      required   pam_securetty.so
    auth      required   pam_nologin.so
    #auth     required   pam_homecheck.so
    auth      required   pam_env.so
    auth      required   pam_mail.so
    account   required   pam_unix2.so   use_ldap
    password  required   pam_pwcheck.s  nullok
    password  required   pam_unix2.so   nullok use_first_pass \
                                        use_authtok use_ldap
    session   required   pam_unix2.so   none use_ldap # debug or trace
    session   required   pam_limits.so
    

    On other Linux systems that do not have an LDAP-enabled pam_unix2.so module, you must edit these files by adding the pam_ldap.so modules as shown here:

    #%PAM-1.0
    auth     required    pam_securetty.so
    auth     required    pam_nologin.so
    auth     sufficient  pam_ldap.so
    auth     required    pam_unix2.so   nullok try_first_pass #set_secrpc
    account  sufficient  pam_ldap.so
    account  required    pam_unix2.so
    password required    pam_pwcheck.so nullok
    password required    pam_ldap.so    use_first_pass use_authtok
    password required    pam_unix2.so   nullok use_first_pass use_authtok
    session  required    pam_unix2.so   none # debug or trace
    session  required    pam_limits.so
    session  required    pam_env.so
    session  optional    pam_mail.so
    

    This example does have the LDAP-enabled pam_unix2.so, but simply demonstrates the use of the pam_ldap.so module. You can use either implementation, but if the pam_unix2.so on your system supports LDAP, you probably want to use it, rather than add an additional module.

Samba-3 PDC Configuration

Verify that the Samba-3.0.2 (or later) packages are installed on each SUSE Linux server before following the steps below. If Samba-3.0.2 (or later) is not installed, you have the choice to either build your own or to obtain the packages from a dependable source. Packages for SUSE Linux 8.2 and 9.0, and Red Hat 9.0 are included on the CD-ROM that is included at the back of this book.

Procedure 6.3. Configuration of PDC Called: MASSIVE

  1. Install the files in ???, ???, ???, and ??? into the /etc/samba/ directory. The three files should be added together to form the smb.conf file.

  2. Verify the contents of the smb.conf file that is generated by Samba as it collates all the included files. You do this by executing:

    root#  testparm -s > test.conf
    

    The output that is created should be free from errors, as shown here:

    Processing section "[homes]"
    Processing section "[printers]"
    Processing section "[apps]"
    Processing section "[netlogon]"
    Processing section "[profiles]"
    Processing section "[profdata]"
    Processing section "[IPC$]"
    Processing section "[accounts]"
    Processing section "[service]"
    Processing section "[pidata]"
    Loaded services file OK.
    

  3. Delete all run-time files from prior Samba operation by executing (for SUSE Linux):

    root#  rm /etc/samba/*tdb
    root#  rm /var/lib/samba/*tdb
    root#  rm /var/lib/samba/*dat
    root#  rm /var/log/samba/*
    

  4. Samba-3 communicates with the LDAP server. The password that it uses to authenticate to the LDAP server must be stored in the secrets.tdb file. Execute the following to create the new secrets.tdb files and store the password for the LDAP Manager:

    root#  smbpasswd -w not24get
    

    The expected output from this command is:

    Setting stored password for "cn=Manager,dc=abmas,dc=biz" in secrets.tdb
    

  5. Samba-3 generates a Windows Security Identifier only when smbd has been started. For this reason, you start Samba. After a few seconds delay, execute:

    root#  smbclient -L localhost -U%
    root#  net getlocalsid
    

    A report such as the following means that the Domain Security Identifier (SID) has not yet been written to the secrets.tdb or to the LDAP backend:

    [2003/12/16 22:32:20, 0] utils/net.c:net_getlocalsid(414)
      Can't fetch domain SID for name: MASSIVE
    

    When the Domain has been created and written to the secrets.tdb file, the output should look like this:

    SID for domain MASSIVE is: S-1-5-21-3504140859-1010554828-2431957765
    

    If, after a short delay (a few seconds), the Domain SID has still not been written to the secrets.tdb file, it is necessary to investigate what may be mis-configured. In this case, carefully check the smb.conf file for typographical errors (the most common problem). The use of the testparm is highly recommended to validate the contents of this file.

  6. When a positive Domain SID has been reported, stop Samba.

  7. Configure the NFS server for your Linux system. So you can complete the steps that follow, enter into the /etc/exports the following entry:

    /home   *(rw,root_squash,sync)
    

    This permits the user home directories to be used on the BDC servers for testing purposes. You, of course, decide what is the best way for your site to distribute data drives, as well as creating suitable backup and restore procedures for Abmas Inc. I'd strongly recommend that for normal operation the BDC is completely independent of the PDC. rsync is a useful tool here as it resembles the NT replication service quite closely. If you do use NFS, do not forget to start the NFS server as follows:

    root#  rcnfs start
    

Your Samba-3 PDC is now ready to communicate with the LDAP password backend. Let's get on with configuration of the LDAP server.

Example 6.4. LDAP Based smb.conf File, Server: MASSIVE global Section: Part A

# Global parameters
[global]
unix charset = LOCALE
workgroup = MEGANET2
netbios name = MASSIVE
interfaces = eth1, lo
bind interfaces only = Yes
passdb backend = ldapsam:ldap://massive.abmas.biz
username map = /etc/samba/smbusers
log level = 1
syslog = 0
log file = /var/log/samba/%m
max log size = 50
smb ports = 139 445
name resolve order = wins bcast hosts
time server = Yes
printcap name = CUPS
show add printer wizard = No
add user script = /var/lib/samba/sbin/smbldap-useradd.pl -a -m '%u'
delete user script = /var/lib/samba/sbin/smbldap-userdel.pl %u
add group script = /var/lib/samba/sbin/smbldap-groupadd.pl -p '%g'
delete group script = /var/lib/samba/sbin/smbldap-groupdel.pl '%g'
add user to group script = /var/lib/samba/sbin/
smbldap-groupmod.pl -m '%u' '%g'
delete user from group script = /var/lib/samba/sbin/
smbldap-groupmod.pl -x '%u' '%g'
set primary group script = /var/lib/samba/sbin/
smbldap-usermod.pl -g '%g' '%u'
add machine script = /var/lib/samba/sbin/
smbldap-useradd.pl -w '%u'
logon script = scripts\logon.bat
logon path = \\%L\profiles\%U
logon drive = X:
domain logons = Yes
preferred master = Yes
wins support = Yes
ldap suffix = dc=abmas,dc=biz
ldap machine suffix = ou=People
ldap user suffix = ou=People
ldap group suffix = ou=Groups

Example 6.5. LDAP Based smb.conf File, Server: MASSIVE global Section: Part B

ldap idmap suffix = ou=Idmap
ldap admin dn = cn=Manager,dc=abmas,dc=biz
idmap backend = ldap:ldap://massive.abmas.biz
idmap uid = 10000-20000
idmap gid = 10000-20000
map acl inherit = Yes
printing = cups
printer admin = Administrator, chrisr

Install and Configure Idealx SMB-LDAP Scripts

The Idealx scripts, or equivalent, are necessary to permit Samba-3 to manage accounts on the LDAP server. You have chosen the Idealx scripts since they are part of the Samba-3 package distribution. On your SUSE Linux system, you find these scripts in the /usr/share/doc/packages/samba3/Examples/LDAP/smbldap-tools directory. On a Red Hat Linux system, they are in a similar path. If you cannot find the scripts on your system, it is easy enough to download them from the Idealx Web Site. The tarbell may be directly downloaded for this site, also.

In your installation, the smbldap-tools are located in /var/lib/samba/sbin. They can be installed in any convenient directory of your choice, in which case you must change the path to them in your smb.conf file on the PDC (MASSIVE).

The scripts are not needed on BDC machines because all LDAP updates are handled by the PDC alone.

  1. Create the /var/lib/samba/sbin directory, and set its permissions and ownership as shown here:

    root#  mkdir -p /var/lib/samba/sbin
    root#  chown root.root /var/lib/samba/sbin
    root#  chmod 755 /var/lib/samba/sbin
    

  2. If you wish to use the downloaded tarbell, unpack the smbldap-tools in a suitable temporary location. Change into either the directory extracted from the tarball, or else into the smbldap-tools directory in your /usr/share/doc/packages directory tree.

  3. Copy all the .pl and .pm files into the /var/lib/samba/sbin directory, as shown here:

    root#  cd /usr/share/doc/packages/samba3/Examples/LDAP/smbldap-tools
    root#  cp *.pl *.pm /var/lib/samba/sbin
    

  4. You must compile the mkntpasswd tool and then install it into the /var/lib/samba/sbin directory, as shown here:

    root#  cd mkntpwd
    root#  make
    gcc  -O2 -DMPU8086  -c -o getopt.o getopt.c
    gcc  -O2 -DMPU8086  -c -o md4.o md4.c
    gcc  -O2 -DMPU8086  -c -o mkntpwd.o mkntpwd.c
    mkntpwd.c: In function `main':
    mkntpwd.c:37: warning: return type of `main' is not `int'
    gcc  -O2 -DMPU8086  -c -o smbdes.o smbdes.c
    gcc  -O2 -DMPU8086  -o mkntpwd getopt.o md4.o mkntpwd.o smbdes.o
    root#  cp mkntpwd /var/lib/samba/sbin
    

    The smbldap-tools scripts must now be configured.

  5. Change to the /var/lib/samba/sbin directory, and edit the /var/lib/samba/sbin/smbldap_conf.pm to affect the changes shown here:

    # Put your own SID
    # to obtain this number do: "net getlocalsid"
    #$SID='S-1-5-21-1671648649-242858427-2873575837';
    $SID='S-1-5-21-3504140859-1010554828-2431957765';
    ...
    # LDAP Suffix
    # Ex: $suffix = "dc=IDEALX,dc=ORG";
    $suffix = "dc=abmas,dc=biz";
    ...
    # Where are stored Users
    # Ex: $usersdn = "ou=Users,$suffix"; ...
    $usersou = q(People);
    $usersdn = "ou=$usersou,$suffix";
    
    # Where are stored Computers
    # Ex: $computersdn = "ou=Computers,$suffix"; ...
    $computersou = q(People);
    $computersdn = "ou=$computersou,$suffix";
    
    # Where are stored Groups
    # Ex $groupsdn = "ou=Groups,$suffix"; ...
    $groupsou = q(Groups);
    $groupsdn = "ou=$groupsou,$suffix";
    
    # Default scope Used
    $scope = "sub";
    
    # Unix password encryption (CRYPT, MD5, SMD5, SSHA, SHA)
    $hash_encrypt="MD5";
    ...
    ############################
    # Credential Configuration #
    ############################
    # Bind DN used
    # Ex: $binddn = "cn=admin,$suffix"; ...
    $binddn = "cn=Manager,$suffix";
    
    # Bind DN passwd used
    # Ex: $bindpasswd = 'secret'; for 'secret'
    $bindpasswd = 'not24get';
    ...
    # Login defs
    # Default Login Shell
    # Ex: $_userLoginShell = q(/bin/bash);
    #$_userLoginShell = q(_LOGINSHELL_);
    $_userLoginShell = q(/bin/bash);
    
    # Home directory prefix (without username)
    # Ex: $_userHomePrefix = q(/home/);
    #$_userHomePrefix = q(_HOMEPREFIX_);
    $_userHomePrefix = q(/home/);
    ...
    # The UNC path to home drives location without the 
    # username last extension (will be dynamically prepended)
    # Ex: q(\\\\My-PDC-netbios-name\\homes)
    # Just comment this if you want to use the smb.conf 
    # 'logon home' directive # and/or desabling roaming profiles
    #$_userSmbHome = q(\\\\_PDCNAME_\\homes);
    $_userSmbHome = q(\\\\MASSIVE\\homes);
    
    # The UNC path to profiles locations without the username 
    # last extension (will be dynamically prepended)
    # Ex: q(\\\\My-PDC-netbios-name\\profiles\\)
    # Just comment this if you want to use the smb.conf 
    # 'logon path' directive and/or desabling roaming profiles
    $_userProfile = q(\\\\MASSIVE\\profiles\\);
    
    # The default Home Drive Letter mapping
    # (automatically mapped at logon time if home directory exists)
    # Ex: q(U:) for U:
    #$_userHomeDrive = q(_HOMEDRIVE_);
    $_userHomeDrive = q(H:);
    ...
    # Allows not to use smbpasswd 
    # (if $with_smbpasswd == 0 in smbldap_conf.pm) but
    # prefer mkntpwd... most of the time, it's a wise choice :-)
    $with_smbpasswd = 0;
    $smbpasswd = "/usr/bin/smbpasswd";
    $mk_ntpasswd = "/var/lib/samba/sbin/mkntpwd";
    ...
    

  6. To complete the configuration of the smbldap-tools, set the permissions and ownership by executing the following commands:

    root#  chown root.root /var/lib/samba/sbin/* 
    root#  chmod 755 /var/lib/samba/sbin/smb*pl 
    root#  chmod 640 /var/lib/samba/sbin/smb*pm 
    root#  chmod 555 /var/lib/samba/sbin/mkntpwd
    

    The smbldap-tools scripts are now ready for use.

LDAP Initialization and Creation of User and Group Accounts

The LDAP database must be populated with well-known Windows Domain user accounts and Domain Group accounts before Samba can be used. The following procedures step you through the process.

At this time, Samba-3 requires that on a PDC all UNIX (Posix) group accounts that are mapped (linked) to Windows Domain Group accounts must be in the LDAP database. It does not hurt to have UNIX user and group accounts in both the system files as well as in the LDAP database. From a UNIX system perspective, the NSS resolver checks system files before referring to LDAP. If the UNIX system can resolve (find) an account in the system file, it does not need to ask LDAP.

Addition of an account to the LDAP backend can be done in a number of ways:

If you always have a user account in the /etc/passwd on every server or in a NIS(+) backend, it is not necessary to add Posix accounts for them in LDAP. In this case, you can add Windows Domain user accounts using the pdbedit utility. Use of this tool from the command line adds the SambaSamAccount entry for the user, but does not add the PosixAccount entry for the user.

If you decide that it is probably a good idea to add both the PosixAccount attributes as well as the SambaSamAccount attributes for each user, then a suitable script is needed. In the example system you are installing in this exercise, you are making use of the Idealx smbldap-tools scripts. A copy of these tools, pre-configured for this system, is included on the enclosed CD-ROM under Chap06/Tools.

If you wish to have more control over how the LDAP database is initialized or want not to use the Idealx smbldap-tools, you should refer to ???.

The following steps initialize the LDAP database, and then you can add user and group accounts that Samba can use. You use the smbldap-populate.pl to seed the LDAP database. You then manually add the accounts shown in ???. The list of users does not cover all 500 network users; it provides examples only.

Note

In the following examples, as the LDAP database is initialized, we do create a container for Computer (machine) accounts. In the Samba-3 smb.conf files, specific use is made of the People container, not the Computers container, for domain member accounts. This is not a mistake; it is a deliberate action that is necessitated by the fact that there is a bug in Samba-3 that prevents it from being able to search the LDAP database for computer accounts if they are placed in the Computers container. By placing all machine accounts in the People container, we are able to side-step this bug. It is expected that at some time in the future this problem will be resolved. At that time, it will be possible to use the Computers container in order to keep machine accounts separate from user accounts.

Table 6.2. Abmas Network Users and Groups

Account NameTypeIDPassword
Robert JordanUserbobjn3v3r2l8
Stanley SorokaUserstansimpl13dst4r
Christine RobersonUserchrisrS9n0nw4ll
Mary VortexisUsermaryvkw13t0n3
AccountsGroupAccounts 
FinancesGroupFinances 
InsuranceGroupPIOps 
  1. Start the LDAP server by executing:

    root#  rcldap start
    Starting ldap-server                           done
    

  2. Change to the /var/lib/samba/sbin directory.

  3. Execute the script that will populate the LDAP database as shown here:

    root#  ./smbldap-populate.pl
    Using builtin directory structure
    adding new entry: dc=abmas,dc=biz
    adding new entry: ou=People,dc=abmas,dc=biz
    adding new entry: ou=Groups,dc=abmas,dc=biz
    adding new entry: ou=Computers,dc=abmas,dc=biz
    adding new entry: uid=Administrator,ou=People,dc=abmas,dc=biz
    adding new entry: uid=nobody,ou=People,dc=abmas,dc=biz
    adding new entry: cn=Domain Admins,ou=Groups,dc=abmas,dc=biz
    adding new entry: cn=Domain Users,ou=Groups,dc=abmas,dc=biz
    adding new entry: cn=Domain Guests,ou=Groups,dc=abmas,dc=biz
    adding new entry: cn=Administrators,ou=Groups,dc=abmas,dc=biz
    adding new entry: cn=Users,ou=Groups,dc=abmas,dc=biz
    adding new entry: cn=Guests,ou=Groups,dc=abmas,dc=biz
    adding new entry: cn=Power Users,ou=Groups,dc=abmas,dc=biz
    adding new entry: cn=Account Operators,ou=Groups,dc=abmas,dc=biz
    adding new entry: cn=Server Operators,ou=Groups,dc=abmas,dc=biz
    adding new entry: cn=Print Operators,ou=Groups,dc=abmas,dc=biz
    adding new entry: cn=Backup Operators,ou=Groups,dc=abmas,dc=biz
    adding new entry: cn=Replicator,ou=Groups,dc=abmas,dc=biz
    adding new entry: cn=Domain Computers,ou=Groups,dc=abmas,dc=biz
    

  4. It is necessary to restart the LDAP server as shown here:

    root#  rcldap restart
    Shutting down ldap-server                            done
    Starting ldap-server                                 done
    

  5. So that we can use a global IDMAP repository the LDAP directory must have a container object for IDMAP data. There are several ways you can check that your LDAP database is able to receive IDMAP information. One of the simplest is to execute:

    root#  slapcat | grep -i idmap
    dn: ou=Idmap,dc=abmas,dc=biz
    ou: idmap
    

    If the execution of this command does not return IDMAP entries, you need to create an LDIF template file (see ???). You can add the required entries using the following command:

    root#  ldapadd -x -D "cn=Manager,dc=abmas,dc=biz" \
    		-w not24get < /etc/openldap/idmap.LDIF
    

    Samba automatically populates this LDAP directory container when it needs to.

  6. It looks like all has gone well, as expected. Let's confirm that this is the case by running a few tests. First we check the contents of the database directly by running slapcat as follows (the output has been cut down):

    root#  slapcat
    dn: dc=abmas,dc=biz
    objectClass: dcObject
    objectClass: organization
    dc: abmas
    o: abmas
    structuralObjectClass: organization
    entryUUID: 5ab02bf6-c536-1027-9d29-b1f32350fb43
    creatorsName: cn=Manager,dc=abmas,dc=biz
    createTimestamp: 20031217234200Z
    entryCSN: 2003121723:42:00Z#0x0001#0#0000
    modifiersName: cn=Manager,dc=abmas,dc=biz
    modifyTimestamp: 20031217234200Z
    ...
    dn: cn=Domain Computers,ou=Groups,dc=abmas,dc=biz
    objectClass: posixGroup
    objectClass: sambaGroupMapping
    gidNumber: 553
    cn: Domain Computers
    description: Netbios Domain Computers accounts
    sambaSID: S-1-5-21-3504140859-1010554828-2431957765-553
    sambaGroupType: 2
    displayName: Domain Computers
    structuralObjectClass: posixGroup
    entryUUID: 5e0a41d8-c536-1027-9d3b-b1f32350fb43
    creatorsName: cn=Manager,dc=abmas,dc=biz
    createTimestamp: 20031217234206Z
    entryCSN: 2003121723:42:06Z#0x0002#0#0000
    modifiersName: cn=Manager,dc=abmas,dc=biz
    modifyTimestamp: 20031217234206Z
    

    This looks good so far.

  7. The next step is to prove that the LDAP server is running and responds to a search request. Execute the following as shown (output has been cut to save space):

    root#  ldapsearch -x -b "dc=abmas,dc=biz" "(ObjectClass=*)"
    # extended LDIF
    #
    # LDAPv3
    # base <dc=abmas,dc=biz> with scope sub
    # filter: (ObjectClass=*)
    # requesting: ALL
    #
    
    # abmas.biz
    dn: dc=abmas,dc=biz
    objectClass: dcObject
    objectClass: organization
    dc: abmas
    o: abmas
    
    # People, abmas.biz
    dn: ou=People,dc=abmas,dc=biz
    objectClass: organizationalUnit
    ou: People
    ...
    # Domain Computers, Groups, abmas.biz
    dn: cn=Domain Computers,ou=Groups,dc=abmas,dc=biz
    objectClass: posixGroup
    objectClass: sambaGroupMapping
    gidNumber: 553
    cn: Domain Computers
    description: Netbios Domain Computers accounts
    sambaSID: S-1-5-21-3504140859-1010554828-2431957765-553
    sambaGroupType: 2
    displayName: Domain Computers
    
    # search result
    search: 2
    result: 0 Success
    
    # numResponses: 20
    # numEntries: 19
    

    Good. It is all working just fine.

  8. You must now make certain that the NSS resolver can interrogate LDAP also. Execute the following commands:

    root#  getent passwd | grep Administrator
    Administrator:x:998:512:Netbios Domain Administrator:/home:/bin/false
    
    root#  getent group | grep Domain
    Domain Admins:x:512:Administrator
    Domain Users:x:513:
    Domain Guests:x:514:
    Domain Computers:x:553:
    

    This demonstrates that the nss_ldap library is functioning as it should.

  9. Our database is now ready for the addition of network users. For each user for whom an account must be created, execute the following:

    root#  ./smbldap-useradd.pl -m -a username
    root#  ./smbldap-passwd.pl username
    Changing password for username
    New password : XXXXXXXX
    Retype new password : XXXXXXXX
    
    root#  smbpasswd username
    New SMB password: XXXXXXXX
    Retype new SMB password: XXXXXXXX
    

    Where username is the login ID for each user.

  10. Now verify that the UNIX (Posix) accounts can be resolved via NSS by executing the following:

    root#  getent passwd
    ...
    Administrator:x:998:512:Netbios Domain Administrator:/home:/bin/false
    nobody:x:999:514:nobody:/dev/null:/bin/false
    bobj:x:1000:513:System User:/home/bobj:/bin/bash
    stans:x:1001:513:System User:/home/stans:/bin/bash
    chrisr:x:1002:513:System User:/home/chrisr:/bin/bash
    maryv:x:1003:513:System User:/home/maryv:/bin/bash
    
    root#  id chrisr
    uid=1002(chrisr) gid=513(Domain Users) groups=513(Domain Users)
    

    This confirms that the UNIX (Posix) user accounts can be resolved from LDAP.

  11. In the above listing, you can see that the user Administrator has been given UID=998. This means that operations conducted from a Windows client using tools such as the Domain User Manager fails under UNIX because the management of user and group accounts requires that the UID=0. You decide to rectify this immediately as demonstrated here:

    root#  cd /var/lib/samba/sbin
    root#  ./smbldap-usermod.pl -u 0 Administrator
    

  12. Make certain that a home directory has been created for every user by listing the directories in /home as follows:

    root#  ls -al /home
    drwxr-xr-x   8 root   root         176 Dec 17 18:50 ./
    drwxr-xr-x  21 root   root         560 Dec 15 22:19 ../
    drwx------   7 bobj   Domain Users     568 Dec 17 01:16 bobj/
    drwx------   7 chrisr Domain Users     568 Dec 17 01:19 chrisr/
    drwx------   7 maryv  Domain Users     568 Dec 17 01:27 maryv/
    drwx------   7 stans  Domain Users     568 Dec 17 01:43 stans/
    

    This is precisely what we want to see.

  13. The final validation step involves making certain that Samba-3 can obtain the user accounts from the LDAP ldapsam passwd backend. Execute the following command as shown:

    root#  pdbedit -Lv chrisr
    Unix username:        chrisr
    NT username:          chrisr
    Account Flags:        [U          ]
    User SID:             S-1-5-21-3504140859-1010554828-2431957765-3004
    Primary Group SID:    S-1-5-21-3504140859-1010554828-2431957765-513
    Full Name:            System User
    Home Directory:       \\MASSIVE\homes
    HomeDir Drive:        H:
    Logon Script:         chrisr.cmd
    Profile Path:         \\MASSIVE\profiles\chrisr
    Domain:               MEGANET2
    Account desc:         System User
    Workstations:
    Munged dial:
    Logon time:           0
    Logoff time:          Mon, 18 Jan 2038 20:14:07 GMT
    Kickoff time:         Mon, 18 Jan 2038 20:14:07 GMT
    Password last set:    Wed, 17 Dec 2003 17:17:40 GMT
    Password can change:  Wed, 17 Dec 2003 17:17:40 GMT
    Password must change: Mon, 18 Jan 2038 20:14:07 GMT
    

    This looks good. Of course, you fully expected that it would all work, didn't you?

  14. Now you add the group accounts that are used on the Abmas network. Execute the following exactly as shown:

    root#  ./smbldap-groupadd.pl -a Accounts
    root#  ./smbldap-groupadd.pl -a Finances
    root#  ./smbldap-groupadd.pl -a PIOps
    

    The addition of groups does not involve keyboard interaction, so the lack of console output is of no concern.

  15. You really do want to confirm that UNIX group resolution from LDAP is functioning as it should. Let's do this as shown here:

    root#  getent group
    ...
    Domain Admins:x:512:Administrator
    Domain Users:x:513:bobj,stans,chrisr,maryv
    Domain Guests:x:514:
    ...
    Accounts:x:1000:
    Finances:x:1001:
    PIOps:x:1002:
    

    The well-known special accounts (Domain Admins, Domain Users, Domain Guests), as well as our own site-specific group accounts, are correctly listed. This is looking good.

  16. The final step we need to validate is that Samba can see all the Windows Domain Groups and that they are correctly mapped to the respective UNIX group account. To do this, just execute the following command:

    root#  net groupmap list
    Domain Admins (S-1-5-21-3504140859-...-2431957765-512) -> Domain Admins
    Domain Users (S-1-5-21-3504140859-...-2431957765-513) -> Domain Users
    Domain Guests (S-1-5-21-3504140859-...-2431957765-514) -> Domain Guests
    ...
    Accounts (S-1-5-21-3504140859-1010554828-2431957765-3001) -> Accounts
    Finances (S-1-5-21-3504140859-1010554828-2431957765-3003) -> Finances
    PIOps (S-1-5-21-3504140859-1010554828-2431957765-3005) -> PIOps
    

    This is looking good. Congratulations it works! Note that in the above output the lines where shortened by replacing the middle value (1010554828) of the SID with the elipsis (...).

  17. The server you have so carefully built is now ready for another important step. You start the Samba-3 server and validate its operation. Execute the following to render all the processes needed fully operative so that, on system reboot, they are automatically started:

    root#  chkconfig named on
    root#  chkconfig dhcpd on
    root#  chkconfig ldap on
    root#  chkconfig nmb on
    root#  chkconfig smb on
    root#  chkconfig winbind on
    root#  rcnmb start
    root#  rcsmb start
    root#  rcwinbind start
    

  18. The next step might seem a little odd at this point, but take note that you are about to start winbindd which must be able to authenticate to the PDC via the localhost interface. This requires a Domain account for the PDC. This account can be easily created by joining the PDC to the Domain by executing the following command:

    root#  net rpc join -U Administrator%not24get
    Joined domain MEGANET2.
    

    This indicates that the Domain security account for the BDC has been correctly created.

  19. At this time it is necessary to restart winbindd so that it can correctly authenticate to the PDC. The following command achieves that:

    root#  rcwinbind restart
    

  20. You may now check Samba-3 operation as follows:

    root#  smbclient -L massive -U%
    
            Sharename      Type      Comment
            ---------      ----      -------
            IPC$           IPC       IPC Service (Samba 3.0.1)
            accounts       Disk      Accounting Files
            service        Disk      Financial Services Files
            pidata         Disk      Property Insurance Files
            apps           Disk      Application Files
            netlogon       Disk      Network Logon Service
            profiles       Disk      Profile Share
            profdata       Disk      Profile Data Share
            ADMIN$         IPC       IPC Service (Samba 3.0.1)
    
            Server               Comment
            ---------            -------
            MASSIVE              Samba 3.0.1
    
            Workgroup            Master
            ---------            -------
            MEGANET2             MASSIVE
    

    This shows that an anonymous connection is working.

  21. For your finale, let's try an authenticated connection. Follow this as shown:

    root#  smbclient //massive/bobj -Ubobj%n3v3r2l8
    smb: \> dir
      .                    D        0  Wed Dec 17 01:16:19 2003
      ..                   D        0  Wed Dec 17 19:04:42 2003
      bin                  D        0  Tue Sep  2 04:00:57 2003
      Documents            D        0  Sun Nov 30 07:28:20 2003
      public_html          D        0  Sun Nov 30 07:28:20 2003
      .urlview             H      311  Fri Jul  7 06:55:35 2000
      .dvipsrc             H      208  Fri Nov 17 11:22:02 1995
    
              57681 blocks of size 524288. 57128 blocks available
    smb: \> q
    

    Well done. All is working fine.

The server MASSIVE is now configured, and it is time to move onto the next task.

Printer Configuration

The configuration for Samba-3 to enable CUPS raw-print-through printing has already been taken care of in the smb.conf file. The only preparation needed for smart printing to be possible involves creation of the directories in which Samba-3 stores Windows printing driver files.

  1. Configure all network attached printers to have a fixed IP address.

  2. Create an entry in the DNS database on the server MASSIVE in both the forward lookup database for the zone abmas.biz.hosts and in the reverse lookup database for the network segment that the printer is to be located in. Example configuration files for similar zones were presented in ??? and in ???.

  3. Follow the instructions in the printer manufacturers' manuals to permit printing to port 9100. Use any other port the manufacturer specifies for direct mode, raw printing. This allows the CUPS spooler to print using raw mode protocols.

  4. Only on the server to which the printer is attached, configure the CUPS Print Queues as follows:

    root#  lpadmin -p printque -v socket://printer-name.abmas.biz:9100 -E
    

    This step creates the necessary print queue to use no assigned print filter. This is ideal for raw printing, i.e., printing without use of filters. The name printque is the name you have assigned for the particular printer.

  5. Print queues may not be enabled at creation. Make certain that the queues you have just created are enabled by executing the following:

    root#  /usr/bin/enable printque
    

  6. Even though your print queue may be enabled, it is still possible that it may not accept print jobs. A print queue will service incoming printing requests only when configured to do so. Ensure that your print queue is set to accept incoming jobs by executing the following commands:

    root#  /usr/bin/accept printque
    

  7. Edit the file /etc/cups/mime.convs to uncomment the line:

    application/octet-stream     application/vnd.cups-raw      0     -
    

  8. Edit the file /etc/cups/mime.types to uncomment the line:

    application/octet-stream
    

  9. Refer to the CUPS printing manual for instructions regarding how to configure CUPS so that print queues that reside on CUPS servers on remote networks route print jobs to the print server that owns that queue. The default setting on your CUPS server may automatically discover remotely installed printers and may permit this functionality without requiring specific configuration.

  10. The following action creates the necessary directory sub-system. Follow these steps to printing heaven:

    root#  mkdir -p /var/lib/samba/drivers/{W32ALPHA,W32MIPS,W32X86,WIN40}
    root#  chown -R root.root /var/lib/samba/drivers
    root#  chmod -R ug=rwx,o=rx /var/lib/samba/drivers
    

Samba-3 BDC Configuration

Procedure 6.7. Configuration of BDC Called: BLDG1

  1. Install the files in ???, ???, and ??? into the /etc/samba/ directory. The three files should be added together to form the smb.conf file.

  2. Verify the smb.conf file as in step 2 of ???.

  3. Carefully follow the steps outlined in ???, taking particular note to install the correct ldap.conf.

  4. Verify that the NSS resolver is working. You may need to cycle the run level to 1 and back to 5 before the NSS LDAP resolver functions. Follow these commands:

    root#  init 1
    

    After the run level has been achieved, you are prompted to provide the root password. Log on, and then execute:

    root#  init 5
    

    When the normal logon prompt appears, log into the system as root and then execute these commands:

    root#  getent passwd
    root:x:0:0:root:/root:/bin/bash
    bin:x:1:1:bin:/bin:/bin/bash
    daemon:x:2:2:Daemon:/sbin:/bin/bash
    lp:x:4:7:Printing daemon:/var/spool/lpd:/bin/bash
    mail:x:8:12:Mailer daemon:/var/spool/clientmqueue:/bin/false
    ...
    Administrator:x:0:512:Netbios Domain Administrator:/home:/bin/false
    nobody:x:999:514:nobody:/dev/null:/bin/false
    bobj:x:1000:513:System User:/home/bobj:/bin/bash
    stans:x:1001:513:System User:/home/stans:/bin/bash
    chrisr:x:1002:513:System User:/home/chrisr:/bin/bash
    maryv:x:1003:513:System User:/home/maryv:/bin/bash
    vaioboss$:x:1005:553:vaioboss$:/dev/null:/bin/false
    bldg1$:x:1006:553:bldg1$:/dev/null:/bin/false
    

    This is the correct output. If the accounts that have UIDs above 512 are not shown, there is a problem.

  5. The next step in the verification process involves testing the operation of UNIX group resolution via the NSS LDAP resolver. Execute these commands:

    root#  getent group
    root:x:0:
    bin:x:1:daemon
    daemon:x:2:
    sys:x:3:
    ...
    Domain Admins:x:512:Administrator
    Domain Users:x:513:bobj,stans,chrisr,maryv,jht
    Domain Guests:x:514:
    Administrators:x:544:
    Users:x:545:
    Guests:x:546:nobody
    Power Users:x:547:
    Account Operators:x:548:
    Server Operators:x:549:
    Print Operators:x:550:
    Backup Operators:x:551:
    Replicator:x:552:
    Domain Computers:x:553:
    Accounts:x:1000:
    Finances:x:1001:
    PIOps:x:1002:
    

    This is also the correct and desired output, because it demonstrates that the LDAP client is able to communicate correctly with the LDAP server (MASSIVE).

  6. You must now set the LDAP administrative password into the Samba-3 secrets.tdb file by executing this command:

    root#  smbpasswd -w not24get
    Setting stored password for "cn=Manager,dc=abmas,dc=biz" in secrets.tdb
    

  7. Now you must obtain the Domain Security Identifier from the PDC and store it into the secrets.tdb file also. This step is not necessary with an LDAP passdb backend because Samba-3 obtains the Domain SID from the sambaDomain object it automatically stores in the LDAP backend. It does not hurt to add the SID to the secrets.tdb, and if you wish to do so, this command can achieve that:

    root#  net rpc getsid MEGANET2
    Storing SID S-1-5-21-3504140859-1010554828-2431957765 \
                               for Domain MEGANET2 in secrets.tdb
    

    When configuring a Samba-3 BDC that has an LDAP backend, there is no need to take any special action to join it to the Domain. However, winbind communicates with the Domain Controller that is running on the localhost and must be able to authenticate, thus requiring that the BDC should be joined to the Domain. The process of joining the Domain creates the necessary authentication accounts.

  8. To join the Samba BDC to the Domain execute the following:

    root#  net rpc join -U Administrator%not24get
    Joined domain MEGANET2.
    

    This indicates that the Domain security account for the BDC has been correctly created.

  9. Verify that user and group account resolution works via Samba-3 tools as follows:

    root#  pdbedit -L
    Administrator:0:Administrator
    nobody:65534:nobody
    bobj:1000:System User
    stans:1001:System User
    chrisr:1002:System User
    maryv:1003:System User
    bldg1$:1006:bldg1$
    
    root#  net groupmap list
    Domain Admins (S-1-5-21-3504140859-...-2431957765-512) -> Domain Admins
    Domain Users (S-1-5-21-3504140859-...-2431957765-513) -> Domain Users
    Domain Guests (S-1-5-21-3504140859-...-2431957765-514) -> Domain Guests
    Administrators (S-1-5-21-3504140859-...-2431957765-544) -> Administrators
    ...
    Accounts (S-1-5-21-3504140859-1010554828-2431957765-3001) -> Accounts
    Finances (S-1-5-21-3504140859-1010554828-2431957765-3003) -> Finances
    PIOps (S-1-5-21-3504140859-1010554828-2431957765-3005) -> PIOps
    

    The above results show that all things are in order.

  10. The server you have so carefully built is now ready for another important step. Now start the Samba-3 server and validate its operation. Execute the following to render all the processes needed fully operative so that, upon system reboot, they are automatically started:

    root#  chkconfig named on
    root#  chkconfig dhcpd on
    root#  chkconfig nmb on
    root#  chkconfig smb on
    root#  chkconfig winbind on
    root#  rcnmb start
    root#  rcsmb start
    root#  rcwinbind start
    

    Samba-3 should now be running and is ready for a quick test. But not quite yet!

  11. Your new BLDG1, BLDG2 servers do not have home directories for users. To rectify this using the SUSE yast2 utility or by manually editing the /etc/fstab file, add a mount entry to mount the home directory that has been exported from the MASSIVE server. Mount this resource before proceeding. An alternate approach could be to create local home directories for users who are to use these machines. This is a choice that you, as system administrator, must make. The following entry in the /etc/fstab file suffices for now:

    massive.abmas.biz:/home  /home  nfs     rw 0 0
    

    To mount this resource, execute:

    root#  mount -a
    

    Verify that the home directory has been mounted as follows:

    root#  df | grep home
    massive:/home         29532988    283388  29249600   1% /home
    

  12. Implement a quick check using one of the users that is in the LDAP database. Here you go:

    root#  smbclient //bldg1/bobj -Ubobj%n3v3r2l8
    smb: \> dir
      .                    D        0  Wed Dec 17 01:16:19 2003
      ..                   D        0  Wed Dec 17 19:04:42 2003
      bin                  D        0  Tue Sep  2 04:00:57 2003
      Documents            D        0  Sun Nov 30 07:28:20 2003
      public_html          D        0  Sun Nov 30 07:28:20 2003
      .urlview             H      311  Fri Jul  7 06:55:35 2000
      .dvipsrc             H      208  Fri Nov 17 11:22:02 1995
    
              57681 blocks of size 524288. 57128 blocks available
    smb: \> q
    

Procedure 6.8. Configuration of BDC Called: BLDG2

  1. Install the files in ???, ???, and ??? into the /etc/samba/ directory. The three files should be added together to form the smb.conf file.

  2. Follow carefully the steps shown in ???, starting at step 2.

Example 6.6. LDAP Based smb.conf File, Server: BLDG1

# Global parameters
[global]
unix charset = LOCALE
workgroup = MEGANET2
netbios name = BLDG1
passdb backend = ldapsam:ldap://massive.abmas.biz
username map = /etc/samba/smbusers
log level = 1
syslog = 0
log file = /var/log/samba/%m
max log size = 50
smb ports = 139 445
name resolve order = wins bcast hosts
printcap name = CUPS
show add printer wizard = No
logon script = scripts\logon.bat
logon path = \\%L\profiles\%U
logon drive = X:
domain logons = Yes
domain master = No
wins server = 172.16.0.1
ldap suffix = dc=abmas,dc=biz
ldap machine suffix = ou=People
ldap user suffix = ou=People
ldap group suffix = ou=Groups
ldap idmap suffix = ou=Idmap
ldap admin dn = cn=Manager,dc=abmas,dc=biz
idmap backend = ldap:ldap://massive.abmas.biz
idmap uid = 10000-20000
idmap gid = 10000-20000
printing = cups
printer admin = Administrator, chrisr

Example 6.7. LDAP Based smb.conf File, Server: BLDG2

# Global parameters
[global]
unix charset = LOCALE
workgroup = MEGANET2
netbios name = BLDG2
passdb backend = ldapsam:ldap://massive.abmas.biz
username map = /etc/samba/smbusers
log level = 1
syslog = 0
log file = /var/log/samba/%m
max log size = 50
smb ports = 139 445
name resolve order = wins bcast hosts
printcap name = CUPS
show add printer wizard = No
logon script = scripts\logon.bat
logon path = \\%L\profiles\%U
logon drive = X:
domain logons = Yes
domain master = No
wins server = 172.16.0.1
ldap suffix = dc=abmas,dc=biz
ldap machine suffix = ou=People
ldap user suffix = ou=People
ldap group suffix = ou=Groups
ldap idmap suffix = ou=Idmap
ldap admin dn = cn=Manager,dc=abmas,dc=biz
idmap backend = ldap://massive.abmas.biz
idmap uid = 10000-20000
idmap gid = 10000-20000
printing = cups
printer admin = Administrator, chrisr

Example 6.8. LDAP Based smb.conf File, Shares Section Part A

[accounts]
comment = Accounting Files
path = /data/accounts
read only = No
[service]
comment = Financial Services Files
path = /data/service
read only = No
[pidata]
comment = Property Insurance Files
path = /data/pidata
read only = No
[homes]
comment = Home Directories
valid users = %S
read only = No
browseable = No
[printers]
comment = SMB Print Spool
path = /var/spool/samba
guest ok = Yes
printable = Yes
browseable = No

Example 6.9. LDAP Based smb.conf File, Shares Section Part B

[apps]
comment = Application Files
path = /apps
admin users = bjordan
read only = No
[netlogon]
comment = Network Logon Service
path = /var/lib/samba/netlogon
guest ok = Yes
locking = No
[profiles]
comment = Profile Share
path = /var/lib/samba/profiles
read only = No
profile acls = Yes
[profdata]
comment = Profile Data Share
path = /var/lib/samba/profdata
read only = No
profile acls = Yes
[print$]
comment = Printer Drivers
path = /var/lib/samba/drivers
browseable = yes
guest ok = no
read only = yes
write list = Administrator, chrisr

Example 6.10. LDIF IDMAP Add-On Load File File: /etc/openldap/idmap.LDIF

dn: ou=Idmap,dc=abmas,dc=biz
objectClass: organizationalUnit
ou: idmap
structuralObjectClass: organizationalUnit

Miscellaneous Server Preparation Tasks

My father would say, “Dinner is not over until the dishes have been done.” The makings of a great network environment take a lot of effort and attention to detail. So far you have completed most of the complex (and to many administrators, the interesting part of server configuration) steps, but remember to tie it all together. Here are a few more steps that must be completed so that your network runs like a well-rehearsed orchestra.

Configuring Directory Share Point Roots

In your smb.conf file, you have specified Windows shares. Each has a path parameter. Even though it is obvious to all, one of the common Samba networking problems is caused by forgetting to verify that every such share root directory actually exists and that it has the necessary permissions and ownership.

Here is an example, but remember to create the directory needed for every share:

root#  mkdir -p /data/{accounts,finsvcs,piops}
root#  mkdir -p /apps
root#  chown -R root.root /data
root#  chown -R root.root /apps
root#  chown -R bobj.Accounts /data/accounts
root#  chown -R bobj.Finances /data/finsvcs
root#  chown -R bobj.PIOps /data/pidata
root#  chmod -R ug+rwxs,o-rwx /data
root#  chmod -R ug+rwx,o+rx-w /apps

Configuring Profile Directories

You made a conscious decision to do everything it would take to improve network client performance. One of your decisions was to implement folder redirection. This means that Windows user desktop profiles are now made up of two components a dynamically loaded part and a set of file network folders.

For this arrangement to work, every user needs a directory structure for the network folder portion of their profile as shown here:

root#  mkdir -p /var/lib/samba/profdata
root#  chown root.root /var/lib/samba/profdata
root#  chmod 755 /var/lib/samba/profdata

# Per user structure
root#  cd /var/lib/samba/profdata
root#  mkdir -p username
root#  for i in InternetFiles Cookies History AppData \
                      LocalSettings MyPictures MyDocuments Recent
root#  do
root#  mkdir username/$i
root#  done
root#  chown -R username.Domain\ Users username
root#  chmod -R 750 username

You have three options insofar as the dynamically loaded portion of the roaming profile is concerned:

  • You may permit the user to obtain a default profile.

  • You can create a mandatory profile.

  • You can create a group profile (which is almost always a mandatory profile).

Mandatory profiles cannot be overwritten by a user. The change from a user profile to a mandatory profile is effected by renaming the NTUSER.DAT to NTUSER.MAN, i.e., just by changing the filename extension.

The location of the profile that a user can obtain is set in the users' account in the LDAP passdb backend. You can manage this using the Idealx smbldap-tools or using the Windows NT4 Domain User Manager.

It may not be obvious that you must ensure that the root directory for the user's profile exists and has the needed permissions. Use the following commands to create this directory:

root#  mkdir -p /var/lib/samba/profiles/username
root#  chown username.Domain\ Users
	    /var/lib/samba/profiles/username
root#  chmod 700  /var/lib/samba/profiles/username

Preparation of Logon Scripts

The use of a logon script with Windows XP Professional is an option that every site should consider. Unless you have locked down the desktop so the user cannot change anything, there is risk that a vital network drive setting may be broken or that printer connections may be lost. Logon scripts can help to restore persistent network folder (drive) and printer connections in a predictable manner. One situation in which such breakage may occur in particular is when a mobile PC (notebook) user attaches to another company's network that forces environment changes that are alien to your network.

If you decide to use network logon scripts, by reference to the smb.conf files for the Domain Controllers, you see that the path to the share point for the NETLOGON share defined is /var/lib/samba/netlogon. The path defined for the logon script inside that share is scripts\logon.bat. This means that as a Windows NT/200x/XP client logs onto the network, it tries to obtain the file logon.bat from the fully qualified path /var/lib/samba/netlogon/scripts. This fully qualified path should, therefore, exist whether you install the logon.bat.

You can, of course, create the fully qualified path by executing:

root#  mkdir -p /var/lib/samba/netlogon/scripts

You should research the options for logon script implementation by referring to TOSHARG, Chapter 21, Section 21.4. A quick Web search will bring up a host of options. One of the most popular logon facilities in use today is called KiXtart.

Windows Client Configuration

In the next few sections, you can configure a new Windows XP Professional disk image on a staging machine. You will configure all software, printer settings, profile and policy handling, and desktop default profile settings on this system. When it is complete, you copy the contents of the C:\Documents and Settings\Default User directory to a directory with the same name in the NETLOGON share on the Domain Controllers.

Much can be learned from the Microsoft Support site regarding how best to set up shared profiles. One knowledge-base article in particular stands out. See: How to Create a Base Profile for All Users.

Configuration of Default Profile with Folder Redirection

Log onto the Windows XP Professional workstation as the local Administrator. It is necessary to expose folders that are generally hidden to provide access to the Default User folder.

Procedure 6.9. Expose Hidden Folders

  1. Launch the Windows Explorer by clicking Start->My Computer->Tools->Folder Options->View Tab. Select Show hidden files and folders, and click OK. Exit Windows Explorer.

  2. Launch the Registry Editor. Click Start->Run. Key in regedt32, and click OK.

Procedure 6.10. Redirect Folders in Default System User Profile

  1. Give focus to HKEY_LOCAL_MACHINE hive entry in the left panel. Click File->Load Hive...->[Panel] Documents and Settings->[Panel] Default User->NTUSER->Open. In the dialog box that opens, enter the key name Default and click OK.

  2. Browse inside the newly loaded Default folder to:

    HKEY_LOCAL_MACHINE\Default\Software\Microsoft\Windows\
                         CurrentVersion\Explorer\User Shell Folders\
    

    The contents of the right panel reveals the contents as shown in ???.

  3. You edit hive keys. Acceptable values to replace the %USERPROFILE% variable includes:

    • A drive letter such as: U:

    • A direct network path such as: \\MASSIVE\profdata

    • A network redirection (UNC name) that contains a macro such as:

      \\%LOGONSERVER%\profdata\

  4. Set the registry keys as shown in ???. Your implementation makes the assumption that users have statically located machines. Notebook computers (mobile users) need to be accommodated using local profiles. This is not an uncommon assumption.

  5. Click back to the root of the loaded hive Default. Click File->Unload Hive...->Yes.

  6. Click File->Exit. This exits the Registry Editor.

  7. Now follow the procedure given in ???. Make sure that each folder you have redirected is in the exclusion list.

  8. You are now ready to copy[11] the Default User profile to the Samba Domain Controllers. Launch Microsoft Windows Explorer, and use it to copy the full contents of the directory Default User that is in the C:\Documents and Settings to the root directory of the NETLOGON share. If the NETLOGON share has the defined UNIX path of /var/lib/samba/netlogon, when the copy is complete there must be a directory in there called Default User.

Procedure 6.11. Reset Folder Display to Original Behavior

  • To launch the Windows Explorer, click Start->My Computer->Tools->Folder Options->View Tab. Deselect Show hidden files and folders, and click OK. Exit Windows Explorer.

Figure 6.3. Windows XP Professional User Shared Folders

Windows XP Professional User Shared Folders

Table 6.3. Default Profile Redirections

Registry KeyRedirected Value
Cache\\%LOGONSERVER%\profdata\%USERNAME%\InternetFiles
Cookies\\%LOGONSERVER%\profdata\%USERNAME%\Cookies
History\\%LOGONSERVER%\profdata\%USERNAME%\History
Local AppData\\%LOGONSERVER%\profdata\%USERNAME%\AppData
Local Settings\\%LOGONSERVER%\profdata\%USERNAME%\LocalSettings
My Pictures\\%LOGONSERVER%\profdata\%USERNAME%\MyPictures
Personal\\%LOGONSERVER%\profdata\%USERNAME%\MyDocuments
Recent\\%LOGONSERVER%\profdata\%USERNAME%\Recent

Configuration of MS Outlook to Relocate PST File

Microsoft Outlook can store a Personal Storage file, generally known as a PST file. It is the nature of email storage that this file grows, at times quite rapidly. So that users' email is available to them at every workstation they may log onto, it is common practice in well-controlled sites to redirect the PST folder to the users' home directory. Follow these steps for each user who wishes to do this.

Note

It is presumed that Outlook Express has been configured for use.

Launch Outlook Express 6. Click Tools->Options->Maintenance->Store Folder->Change.

Follow the on-screen prompts to relocate the PST file to the desired location.

Configure Delete Cached Profiles on Logout

To configure the Windows XP Professional client to auto-delete roaming profiles on logout:

Click Start->Run. In the dialog box, enter: MMC and click OK.

Follow these steps to set the default behavior of the staging machine so that all roaming profiles are deleted as network users log out of the system. Click File->Add/Remove Snap-in->Add->Group Policy->Add->Finish->Close->OK.

The Microsoft Management Console now shows the Group Policy utility that enables you to set the policies needed. In the left panel, click Local Computer Policy->Administrative Templates->System->User Profiles. In the right panel, set the properties shown here by double-clicking on each item as shown:

  • Do not check for user ownership of Roaming Profile Folders = Enabled

  • Delete cached copies of roaming profiles = Enabled

Close the Microsoft Management Console. The settings take immediate effect and persist onto all image copies made of this system to deploy the new standard desktop system.

Uploading Printer Drivers to Samba Servers

Users want to be able to use network printers. You have a vested interest in making it easy for them to print. You have chosen to install the printer drivers onto the Samba servers and to enable point-and-click (drag-and-drop) printing. This process results in Samba being able to automatically provide the Windows client with the driver necessary to print to the printer chosen. The following procedure must be followed for every network printer:

  1. Join your Windows XP Professional workstation (the staging machine) to the MEGANET2 Domain. If you are not sure of the procedure, follow the guidance given in ???.

  2. After the machine has re-booted, log onto the workstation as the domain Administrator.

  3. Launch MS Windows Explorer. Navigate in the left panel. Click My Network Places->Entire Network->Microsoft Windows Network->Meganet2->Massive. Click on Massive Printers and Faxes.

  4. Identify a printer that is shown in the right panel. Let us assume the printer is called ps01-color. Right-click on the ps01-color icon and select the Properties entry. This opens a dialog box that indicates that “The printer driver is not installed on this computer. Some printer properties will not be accessible unless you install the printer driver. Do you want to install the driver now?” It is important at this point you answer No.

  5. The printer properties panel for the ps01-color printer on the server MASSIVE is displayed. Click the Advanced tab. Note that the box labelled Driver is empty. Click the New Driver button that is next to the Driver box. This launches the quote“Add Printer Wizard”.

  6. The “Add Printer Driver Wizard on MASSIVE” panel is now presented. Click Next to continue. From the left panel, select the Printer Manufacturer. In your case, you are adding a driver for a printer manufactured by Lexmark. In the right panel, select the printer (Lexmark Optra Color 40 PS). Click Next, and then Finish to commence driver upload. A progress bar appears and instructs you as each file is being uploaded and that it is being directed at the network server \\massive\ps01-color.

  7. The driver upload completes in anywhere from a few seconds to a few minutes. When it completes, you are returned to the Advanced tab in the Properties panel. You can set the Location (under the General tab), and Security settings (under the Security tab). Under the Sharing tab it is possible to load additional printer drivers, there is also a check-box in this tab called “List in the directory”. When this box is checked the printer will be published in Active Directory (Applicable to Active Directory use only.)

  8. Click OK. It will take a minute or so to upload the settings to the server. You are now returned to the Printers and Faxes on Massive monitor. Right-click on the printer, click Properties->Device Settings. Now change the settings to suit your requirements. BE CERTAIN TO CHANGE AT LEAST ONE SETTING and apply the changes even if you need to reverse them changes back to their original settings.

  9. This is necessary so that the printer settings are initialized in the Samba printers database. Click Apply to commit your settings. Revert any settings you changed just to initialize the Samba printers database entry for this printer. If you need to revert a setting, Click Apply again.

  10. Verify that all printer settings are at the desired configuration. When you are satisfied that they are, click the General tab. Now click the Print Test Page button. A test page should print. Verify that it has printed correctly. Then click OK in the panel that is newly presented. Click OK on the ps01-color on massive Properties panel.

  11. You must repeat this process for all network printers (i.e., for every printer, on each server). When you have finished uploading drivers to all printers, close all applications. The next task is to install software your users require to do their work.

Software Installation

Your network has both fixed desktop workstations as well as notebook computers. As a general rule, it is a good idea to not tamper with the operating system that is provided by the notebook computer manufacturer. Notebooks require special handling that is beyond the scope of this chapter.

For desktop systems, the installation of software onto administratively centralized application servers make a lot of sense. This means that you can manage software maintenance from a central perspective and that only minimal application stub-ware needs to be installed onto the desktop systems. You should proceed with software installation and default configuration as far as is humanly possible and so long as it makes sense to do so. Make certain to thoroughly test and validate every aspect of software operations and configuration.

When you believe that the overall configuration is complete, be sure to create a shared group profile and migrate that to the Samba server for later re-use when creating custom mandatory profiles, just in case a user may have specific needs you had not anticipated.

Roll-out Image Creation

The final steps before preparing the distribution Norton Ghost image file you might follow are:

Un-join the domain Each workstation requires a unique name and must be independently joined into Domain Membership.

Defragment the hard disk While not obvious to the uninitiated, defragmentation results in better performance and often significantly reduces the size of the compressed disk image. That also means it will take less time to deploy the image onto 500 workstations.

Key Points Learned

This chapter has introduced many new concepts. Is it a sad fact that the example presented deliberately avoided any consideration of security. Security does not just happen; you must design it into your total network. Security begins with a systems design and implementation that anticipates hostile behavior from users both inside and outside the organization. Hostile and malicious intruders do not respect barriers; they accept them as challenges. For that reason, if not simply from a desire to establish safe networking practices, you must not deploy the design presented in this book in an environment where there is risk of compromise.

As a minimum, the LDAP server must be protected by way of Access Control Lists (ACLs) and it must be configured to use secure protocols for all communications over the network. Of course, secure networking does not result just from systems design and implementation but involves constant user education training, and above all disciplined attention to detail and constant searching for signs of unfriendly or alien activities. Security is itself a topic for a whole book. Please do consult appropriate sources. Jerry Carter's book LDAP System Administration is a good place to start reading about OpenLDAP as well as security considerations.

The substance of this chapter that has been deserving of particular attention includes:

  • Implementation of an OpenLDAP-based passwd backend necessary to support distributed Domain Control.

  • Implementation of Samba Primary and Secondary Domain Controllers with a common LDAP backend for user and group accounts that is shared with the UNIX system through the PADL nns_ldap and pam_ldap toolsets.

  • Use of the Idealx smbldap-tools scripts for UNIX (Posix) account management as well as to manage Samba Windows user and group accounts.

  • The basics of implementation of Group Policy controls for Windows network clients.

  • Control over roaming profiles, with particular focus on folder redirection to network drives.

  • Use of the CUPS printing system together with Samba-based printer driver auto-download.

Questions and Answers

Well, here we are at the end of this chapter and we have only ten questions to help you to remember so much. There are bound to be some sticky issues here.

Why did you not cover secure practices? Isn't it rather irresponsible to instruct network administrators to implement insecure solutions?
You have focused much on SUSE Linux and little on the market leader, Red Hat. Do you have a problem with Red Hat Linux? Doesn't that make your guidance irrelevant to the Linux I might be using?
You did not use SWAT to configure Samba. Is there something wrong with it?
You have exposed a well-used password not24get. Is that not irresponsible?
The Idealx smbldap-tools create many domain group accounts that are not used. Is that a good thing?
Can I use LDAP just for Samba accounts and not for UNIX system accounts?
Why are the Windows Domain RID portions not the same as the UNIX UID?
Printer configuration examples all show printing to the HP port 9100. Does this mean that I must have HP printers for these solutions to work?
Is folder redirection dangerous? I've heard that you can lose your data that way.
Is it really necessary to set a local Group Policy to exclude the redirected folders from the roaming profile?

Why did you not cover secure practices? Isn't it rather irresponsible to instruct network administrators to implement insecure solutions?

Let's get this right. This is a book about Samba, not about OpenLDAP and secure communication protocols for subjects other than Samba. Earlier on, you note that the Dynamic DNS and DHCP solutions also used no protective secure communications protocols. The reason for this is simple: There are so many ways of implementing secure protocols that this book would have been even larger and more complex.

The solutions presented here all work (at least they did for me). Network administrators have the interest and the need to be better trained and instructed in secure networking practices and ought to implement safe systems. I made the decision, right or wrong, to keep this material as simple as possible. The intent of this book is to demonstrate a working solution and not to discuss too many peripheral issues.

This book makes little mention of backup techniques. Does that mean that I am recommending that you should implement a network without provision for data recovery and for disaster management? Back to our focus: The deployment of Samba has been clearly demonstrated.

You have focused much on SUSE Linux and little on the market leader, Red Hat. Do you have a problem with Red Hat Linux? Doesn't that make your guidance irrelevant to the Linux I might be using?

Both Red Hat Linux and SUSE Linux comply with the Linux Standards Base specifications for a standard Linux distribution. The differences are marginal. Surely you know your Linux platform and you do have access to administration manuals for it. This book is not a Linux tutorial; it is a Samba tutorial. Let's keep the focus on the Samba part of the book; all the other bits are peripheral (but important) to creation of a total network solution.

What I find interesting is the attention reviewers give to Linux installation and to the look and feel of the desktop, but does that make for a great server? In this book, I have paid particular attention to the details of creating a whole solution framework. I have not tightened every nut and bolt, but I have touched on all the issues you need to be familiar with. Over the years many people have approached me wanting to know the details of exactly how to implement a DHCP and Dynamic DNS server with Samba and WINS. In this chapter, it is plain to see what needs to be configured to provide transparent interoperability. Likewise for CUPS and Samba interoperation. These are key stumbling areas for many people.

At every critical junction, I have provided comparative guidance for both SUSE and Red Hat Linux. Both manufacturers have done a great job in furthering the cause of open source software. I favor neither and respect both. I like particular features of both products (companies also). No bias in presentation is intended. Oh, before I forget, I particularly like Debian Linux; that is my favorite playground.

You did not use SWAT to configure Samba. Is there something wrong with it?

That is a good question. As it is, the smb.conf file configurations are presented in as direct a format as possible. Adding SWAT into the equation would have complicated matters. I sought simplicity of implementation. The fact is that I did use SWAT to create the files in the first place.

There are people in the Linux and open source community who feel that SWAT is dangerous and insecure. Many will not touch it with a barge-pole. By not introducing SWAT, I hope to have brought their interests on board. SWAT is well covered is TOSHARG.

You have exposed a well-used password not24get. Is that not irresponsible?

Well, I had to use a password of some sort. At least this one has been consistently used throughout. I guess you can figure out that in a real deployment it would make sense to use a more secure and original password.

The Idealx smbldap-tools create many domain group accounts that are not used. Is that a good thing?

I took this up with Idealx and found them most willing to change that in the next version. Let's give Idealx some credit for the contribution they have made. I appreciate their work and, besides, it does no harm to create accounts that are not now used as at some time Samba may well use them.

Can I use LDAP just for Samba accounts and not for UNIX system accounts?

Yes, you can do that for user accounts only. Samba requires there to be a Posix (UNIX) group account for every Windows Domain group account. But if you put your users into the system password account, how do you plan to keep all domain controller system password files in sync? I think that having everything in LDAP makes a lot of sense for the UNIX admin who is still learning the craft and is migrating from MS Windows.

Why are the Windows Domain RID portions not the same as the UNIX UID?

Samba uses a well-known public algorithm for assigning RIDs from UIDs and GIDs. This algorithm ought to ensure that there will be no clashes with well-known RIDs. Well-known RIDs have special significance to MS Windows clients. The automatic assignment used the calculation: RID = UID x 2 + 1000. Of course, Samba does permit you to override that to some extent. See the smb.conf man page entry for algorithmic rid base.

Printer configuration examples all show printing to the HP port 9100. Does this mean that I must have HP printers for these solutions to work?

No. You can use any type of printer and must use the interfacing protocol supported by the printer. Many networks use LPR/LPD print servers to which are attached PCL printers, InkJet printers, plotters, and so on. At home I use a USB attached Inject printer. Use the appropriate device URI (Universal Resource Interface) argument to the lpadmin -v option that is right for your printer.

Is folder redirection dangerous? I've heard that you can lose your data that way.

The only loss of data I know of that involved folder redirection was caused by manual misuse of the redirection tool. The administrator redirected a folder to a network drive and said he wanted to migrate (move) the data over. Then he changed his mind, so he moved the folder back to the roaming profile. This time, he declined to move the data because he thought it was still in the local profile folder. That was not the case, so by declining to move the data back, he wiped out the data. You cannot hold the tool responsible for that. Caveat emptor still applies.

Is it really necessary to set a local Group Policy to exclude the redirected folders from the roaming profile?

Yes. If you do not do this, the data will still be copied from the network folder (share) to the local cached copy of the profile.



[11] There is an alternate method by which a Default User profile can be added to the NETLOGON share. This facility in the Windows System tool permits profiles to be exported. The export target may be a particular user or group profile share point, or else into the NETLOGON share. In this case, the profile directory must be named Default User.