Mac OS X Directory Services v10.6: Accessing an Active Directory Service

This chapter is from the book 

Active Directory is Microsoft’s directory services solution that provides LDAP and Kerberos services for identification and authentication. Many organizations with Windows computers use Active Directory because it provides these features:

• Security and policy management for Windows computers
• Tight integration with popular application servers such as Microsoft Exchange and Microsoft SQL Server
• High availability, with the ability to place multiple replica servers across geographic locations in a multimaster configuration

It is easy to integrate Mac OS X into an Active Directory environment. Although Mac OS X computers can access directory information provided by Active Directory via the LDAPv3 connector, you should use the Active Directory connector, which provides the following capabilities:

• Creating a computer account for secure communication with Active Directory services
• Configuring mappings of Open Directory objects and attributes to Active Directory objects and attributes
• Setting up the Kerberos environment for seamless integration with Active Directory
• Enabling SMB packet signing and packet encryption
• Support of Active Directory password policies
• Support of Active Directory sites, which directs Windows and Mac OS X client computers to the most appropriate services based on their IP network
• Caching information from Active Directory services so that Mac OS X computers can use the information even if they are not connected to the network

In this chapter you will learn how to use System Preferences, Directory Utility, and the command line to bind to Active Directory, and to modify the default settings for the Active Directory connector to enable login and access to a network home folder. You will learn how to overcome problems with your initial bind to Active Directory, and you will learn troubleshooting techniques for login problems with an Active Directory user account.

Mac OS X v10.6 brings numerous improvements to the Active Directory connector, from better caching to improved support for Windows Server 2008 domains.

Configuring Mac OS X to Log In Using Active Directory

You can use the Accounts pane of System Preferences, Directory Utility, or dsconfigad to bind a Mac OS X client computer to an Active Directory domain. dsconfigad allows you to configure some features that Directory Utility does not expose, but if you use dsconfigad you need to take some additional steps (such as enabling the Active Directory connector and adding the Active Directory node to your search paths). Before you bind, however, you need to know a few things about your Active Directory service.

Understanding Active Directory Terms

When you bind to Active Directory, you need to know the domain name and you must have the credentials of a user who has authorization to join computers to Active Directory.

A domain is the building block of Active Directory; it is a collection of directory objects such as users, groups, and computers. An Active Directory domain requires a domain controller, which can be a computer running any version of Windows Server 2000 through Windows Server 2008. A domain is identified by its DNS namespace; for example, the server windows-server.pretendco.com may be a domain controller for the domain pretendco.com. Active Directory relies on DNS records generated by a DNS service that is tightly integrated with Active Directory, so you should configure Mac OS X to use the DNS service associated with the Active Directory domain before attempting to bind.

A tree is one or more domains in a contiguous name space. A forest is a set of domain trees that have a common schema and global catalog, which is used to describe a best-effort collection of all the resources in a domain. The global catalog is commonly used for email address lookups.

Like standard Windows clients, Mac OS X binds to only one Active Directory domain at a time.

Understanding the Active Directory Computer Object

When you bind a Mac OS X client computer to Active Directory, you use or create a computer object for Mac OS X. Just like user objects, computer objects are used for identification, authentication, and authorization. The computer object has rights to do certain things, such as to bind and update its own DNS record.

When you bind a Mac OS X computer to Active Directory, Mac OS X uses the user credentials you supply to set up a computer object and password in Active Directory. This password is a shared secret between your Mac OS X computer and the Active Directory service. Your Mac OS X computer uses this password to authenticate to Active Directory and set up a secure channel to enable your Mac OS X computer to communicate with Active Directory. The password is randomly generated, and it is unrelated to the user account you use to perform the bind. For more information, see the section “Confirming Your Active Directory Connector and the Samba Service Are Using the Same Active Directory Computer Password” in Chapter 8.

If you delete the computer object or reset the computer object password in Active Directory, you need to rebind Mac OS X to Active Directory in order for Mac OS X to access Active Directory.

When you use System Preferences or Directory Utility to bind to Active Directory, you see a suggested computer ID to use for the name of the Active Directory computer object. This computer ID is based on your host name (if you use the Accounts preference) or your Bonjour name (if you use Directory Utility). Regardless of what you enter as a computer ID, Mac OS X will use only the lowercase characters a–z, 0–9, dash (-), and underscore (_), in order for Mac OS X file sharing to be compatible with legacy Windows computers. If your computer name is longer than 15 characters, you may experience errors when binding to Active Directory. Each computer should use the same Mac OS X computer name and Active Directory computer name to help keep track of computer names, unless you have a good reason not to do so.

Specifying a User to Create the Computer Object

When binding to Active Directory, you need to supply the credentials of an Active Directory administrator or user who is authorized to create computer objects. By default, you can use a regular Active Directory user to bind to Active Directory ten times, but after that you will encounter an error. “Troubleshooting Binding Issues,” later in this chapter, offers some solutions for this problem.

Binding to Active Directory with System Preferences

The simplest way to bind Mac OS X to Active Directory is to use the Accounts pane of System Preferences. The steps are as follows:

1. Open System Preferences.
2. Click Accounts.
3. Click Login Options.
4. Click Join next to Network Account Server.
   

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   NOTE

   If you are already bound to another directory node, an Edit button appears instead of Join; click Edit.

5. In the Server field, enter the name of the Active Directory domain—in other words, “pretendco.com” not “windows-server.pretendco.com.”
   

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   NOTE

   If you are already bound to another directory node, you must first click the Add (+) button.

   This can be any domain in the forest, but remember that the domain name is the DNS namespace of the domain, not the DNS name of the domain controller.

6. In the Computer ID field, enter the name of the Active Directory computer object to use for this Mac OS X computer. By default, this displays your host name, which may be determined from a DNS record that matches your IP address, or your Bonjour name, if there is no matching DNS record.
7. In the AD Admin User field, enter the name of an Active Directory administrator or the name of an Active Directory user who can join a computer to the domain.
8. In the AD Admin Password field, enter the password for the user you specified in step 7.
   

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9. Click OK, and then provide a local administrator’s credentials when prompted. Mac OS X attempts to bind to Active Directory with the default settings.

The Network Account Server field now displays a green status indicator along with the name of the Active Directory domain.

If you are bound to multiple directories, the Network Account Server field simply displays the dimmed text Multiple.

Binding to Active Directory with Directory Utility

Instead of the Accounts preference, you could use Directory Utility to bind to Active Directory, just like you would have with Mac OS X v10.5 and earlier. The process is very similar—you can click the Open Directory Utility button on the Login Options pane of the Accounts preference (shown in the figure below step 4 of the preceding exercise), or open Directory Utility directly from /System/Library/CoreServices/. You must specify the Active Directory domain as you did in the preceding exercise. Directory Utility offers more choices and advanced options, and it will be covered later in this chapter.

Logging In as an Active Directory User on Mac OS X

Once you bind your Mac OS X computer to Active Directory, you can log in with your Active Directory user account at your Mac OS X login window. By default, when you log in with an Active Directory user account, the following things are true:

• If your password will expire soon, you have the opportunity to change it during the login process.
  

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• Your home folder is located on the startup volume.
• Active Directory grants you a Kerberos Ticket Granting Ticket (TGT) as part of the login process. You can confirm this by opening the Ticket Viewer application (in /System/Library/CoreServices).
  

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Also note that in Mac OS X v10.6, the default preference for the Finder is to not display hard disks and or connected servers, so no items will be displayed on the desktop.

Specifying a User Name at the Login Screen

By default, when you are bound to another directory node, the Mac OS X login window also displays the option of “Other.” This allows you to specify a user name from a different directory node, as shown in this figure:

When you select Other, the login window reveals a field for Name and Password.

At the Mac OS X login window, you can use many combinations of the user identifiers “Full name,” “User login name,” or “User login name (Pre-Windows 2000)” from Active Directory, along with other elements of the domain name. Consider the figure below, which shows a user created with Active Directory tools.

You can log in with any of the following names in the Name field in the Mac OS X login window:

• schoun-regan
• sregan
• Schoun Regan
• schoun-regan@pretendco.com
• sregan@pretendco.com
• Schoun Regan@pretendco.com
• PRETENDCO\schoun-regan
• PRETENDCO\sregan
• PRETENDCO\Schoun Regan

Understanding the Home Folder Default Behavior

When you log in with a user account for Active Directory, by default Mac OS X creates a home folder for the user on the startup volume in /Users/usershortname.

If a directory already exists with that name, Mac OS X will not create a new home folder. You may experience unexpected results because the Active Directory user does not have write permissions to the home folder.

See the section “Transitioning from a Local User to an Active Directory User” later in this chapter, if that is appropriate for your situation.

Understanding Home Folder Synchronization

The default settings do not configure Mac OS X to synchronize the local home folder with a network home folder. If you log in as the same Active Directory user on multiple Mac OS X computers that are configured with the default settings for the Active Directory connector, you will have a different home folder on each computer, and the contents will not be synchronized. To prevent this situation, you can do the following:

• Configure mobile accounts and home folder synchronization. See the section “Understanding Mobile Accounts” for more on this.
• Deselect the option to force the creation of a local home folder, and then use Active Directory tools to assign a network home folder for the Active Directory user account. See the “Specifying a Network Home Folder” section for details.

Changing the Active Directory Connector Default Settings

The Active Directory connector’s default settings might not meet your needs. For instance, you may want to not force local home folders on the startup volume, or you may want to specify Active Directory groups whose members will be considered local administrators when they authenticate locally on your Mac OS X computer. In this section you will learn how to use Directory Utility and the command line to configure some of the advanced options of the Active Directory connector.

Follow these steps to use Directory Utility to access Active Directory Advanced Options:

1. Open Directory Utility (in /System/Library/CoreServices). If necessary, click the lock in the lower-left corner and provide credentials for a local administrator.
2. In the toolbar, click Services.
3. Make sure the Active Directory Service checkbox is selected.
4. Select the Active Directory service.
5. In the lower-left corner of the Directory Utility window, click the Edit button.
6. Click the disclosure triangle next to Show Advanced Options.

Exploring the “User Experience” Advanced Options Pane

The default pane for Directory Utility’s Advanced Options is the User Experience pane.

The first option, “Create mobile account at login,” is disabled by default. A mobile account caches user credentials locally so they can be used when the computer is not connected to the directory node. See the “Understanding Mobile Accounts” section for more details about mobile accounts and synchronized home folders.

The “Force local home directory on startup disk” option is enabled by default. If you enable this option, Mac OS X creates a local home folder in /Users/username when an Active Directory user logs in (unless a local home folder already exists at that location).

Specifying a Network Home Folder

There are at least two possible ways to specify a network home folder for an Active Directory user account:

• If your Active Directory schema has been extended to support Apple objects and attributes, map dsAttrTypeStandard:HomeDirectory to an extended attribute in your user record; then you can use Workgroup Manager to specify the home folder.
• Select the “Use UNC path from Active Directory to derive network home location” checkbox and use Active Directory tools to populate the Home Folder field for an Active Directory user. The Active Directory connector maps dsAttrTypeStandard:SMBHomeDirectory to Active Directory’s dsAttrTypeNative:homeDirectory. You can also specify this option with the -uncpath option of dsconfigad.

You must specify which file-sharing protocol to use: SMB or AFP (Apple Filing Protocol). SMB is the default setting, so it is easy to use Windows file services to host home folders for Active Directory users who log in to a Mac OS X computer.

Mac OS X has had full support for SMB packet signing since Mac OS X v10.5, a security feature (designed to prevent man-in-the-middle attacks) enabled by default on Windows Server 2003 SP1 and later. Many Windows Server administrators require client computers to use this option, which makes it impossible for computers using earlier versions of Mac OS X to access their SMB share points without installing third-party SMB client software.

AFP offers some advantages over SMB as a file service protocol for Mac OS X client computers: It is faster, native to Mac OS X, supports Time Machine and network Spotlight searching, and handles a wider range of filenames in a mixed environment. Unfortunately, Windows servers do not offer AFP by default.

Although Windows Server 2003 and earlier can offer AFP via Services for Macintosh (SFM), the SFM version of AFP is not current. For example, SFM supports only 31 characters in a filename, which causes a problem when Mac OS X uses a long filename, such as ~/Library/Preferences/ByHost/com.apple.iCal.helper.0017f3e00523.plist. SFM is not recommended for Mac OS X network home folders. If you must use your Windows server for network home directories, consider running a third-party AFP file service, such as GroupLogic’s ExtremeZ-IP, on your Windows server.

You can use a Mac OS X Server to host network home folders for Active Directory users, whether they log in to Mac OS X computers or Windows computers. You can use Mac OS X Server’s AFP service for users who log in to Mac OS X computers, and Mac OS X Server’s SMB service for users who log in to Windows computers. Discourage users from simultaneously logging in as the same user on Mac OS X and Windows computers, because editing the same file over two different protocols simultaneously could corrupt the file.

For more information about offering file services from a Mac OS X Server, see Chapter 4, “Using File Services,” in Apple Training Series: Mac OS X Server Essentials v10.6.

Logging In with a Windows Home Folder

If you use Active Directory tools to define a network home folder (dsAttrTypeNative:SMBHome) for the user, Mac OS X mounts the network volume that contains that Active Directory home folder. Unless you specify otherwise, by default the Active Directory connector creates a local home folder on the startup volume, so Mac OS X mounts the Windows home folder but does not use it as the user’s home folder.

The network folder appears in the Dock, but the volume does not appear on the user’s desktop by default. The default preference for the Finder in Mac OS X v10.6 is to not display mounted network volumes on the desktop. To change this in the Finder, choose Finder > Preferences and select the checkbox for “Connected servers.”

When an Active Directory user with a valid Windows home folder (dsAttrTypeStandard:SMBHome) logs in to a Mac OS X computer that does not have the “Force local home directory on startup disk” option enabled in the User Experience pane of the Active Directory connector, that user’s home folder will be on a network server as expected. You may see question marks in the user’s Dock, which represent the user’s Documents and Downloads folders, which are not created automatically on Windows servers. If the network home folder is hosted on a Mac OS X Server file service, and you configured the Active Directory connector to use SMB rather than AFP, you should create the user’s home folder on the Mac OS X server that hosts the home folder before the user logs in for the first time, so that the user has a home folder with the set of standard folders. By default, Mac OS X Server will create a home folder automatically if a user makes an AFP connection, but not an SMB connection.

If you deselect both the “Force local home directory on startup disk” and “Use UNC path from Active Directory to derive network home location” checkboxes, and an Active Directory user with no valid home folder defined attempts to log in, that user will not be able to log in at the Mac OS X login window; the login window will shake after an unsuccessful authentication and return to the login window.

Changing User and Group Mappings

By default, the Active Directory connector generates a unique user ID, or UID—dsAttrTypeStandard:UniqueID—for an Active Directory user record based on that user’s GUID attribute. The calculated UniqueID is unique across the domain, yet consistent across every Mac OS X computer in the domain. Likewise, the Active Directory connector generates a unique integer for each Active Directory group record as well (dsAttrTypeStandard:PrimaryGroupID).

However, if you have extended your Active Directory schema, or if you have appropriate values populated in the RFC2307 attributes (which are already part of the Active Directory schema in domains hosted by Windows Server 2003R2 and later, but are not populated by default), then you can use the Mappings pane to access these attributes.

Be forewarned that if you change the mappings (after using Active Directory with the default mappings), users may lose access to files that they previously owned or could access.

The Mappings pane, shown in the following figure, allows you to change the mappings for the following standard attributes:

• UID—dsAttrTypeStandard:UniqueID
• User GID—dsAttrTypeStandard:PrimaryGroupID
• Group GID—dsAttrTypeStandard:PrimaryGroupID

If the Active Directory schema is extended with Microsoft’s Services for UNIX (SFU), and the attributes contain valid values, you can:

• Map UID to msSFU-30-Uid-Number
• Map both user GID and group GID to msSFU-30-Gid-Number

If the Active Directory schema has RFC2307 attributes that are populated with valid values, you can:

• Map UID to uidNumber
• Map both user GID and group GID to gidNumber

If the Active Directory schema is extended with Apple object classes and attributes, and the attributes are populated, you can:

• Map UID to UniqueID
• Map user GID to PrimaryGroupID
• Map group GID to gidNumber

Exploring the “Administrative” Advanced Options Pane

The “Prefer this domain server” option is one of the most misunderstood features of the Active Directory connector. If you select the “Prefer this domain server” checkbox and specify an Active Directory domain controller, the Active Directory connector will prefer that server if your Mac OS X computer is contained within the same Active Directory site as the specified domain controller.

Use the “Allow administration by” option to enable any user of the Active Directory groups that you specify to be in the group of local administrators for this Mac OS X computer. This is useful if you create an Active Directory group and populate it with users who should have the authority to administer the Mac OS X computers in your organization.

Restricting Authentication to Specific Domains

When you add Active Directory to your search path, Mac OS X automatically adds the node Active Directory/All Domains to your search path by default. If you want to restrict the authentication search path to use specific domains in your forest only, follow these steps:

1. Deselect the option “Allow authentication from any domain in the forest,” and then click OK to dismiss the Active Directory services pane.
2. In the toolbar of Directory Utility, click Search Policy, and then click the Authentication tab.
3. Select Active Directory/All Domains, click the Remove (–) button in the lower-left corner of the Directory Utility window, and then click OK at the confirmation dialog.
4. Click the Add (+) button in the lower-left corner of the Directory Utility window. Directory Utility displays a list of the domains in your forest. Select the domains you want to enable in your authentication search path, and then click Add.
   

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5. Click Apply to activate the change.

Creating the Computer Account in a Custom Location

Unless you specify otherwise, the Active Directory connector creates computer objects in the CN=Computers container with the domain that you join. Depending on the configuration of your domain controller, this may not be correct. For example, some administrators have a special container (CN) or organizational unit (OU) for all Mac OS X computers.

Use the following steps to configure the Active Directory connector to add the computer to the container OU=Macs,DC=pretendco,DC=com. Rather than binding from the Accounts pane of System Preferences, you will bind from Directory Utility’s Active Directory services pane, which offers different binding options.

1. Open Directory Utility. If necessary, click the lock icon in the lower-left corner and provide credentials for a local administrator.
2. In the toolbar, click Services.
3. Make sure the Active Directory service checkbox is selected.
4. Select the Active Directory service.
5. In the lower-left corner of the Directory Utility window, click the Edit button.

   If you are not already bound to Active Directory, Directory Utility displays the dialog shown in the following figure. If you are already bound, you must first unbind in order to change the location of your computer account (in this case, simply click Unbind).

   

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6. In the Active Directory Domain field, enter the Active Directory domain.
7. In the Computer ID field, enter the name of the Active Directory computer object to use for this Mac OS X computer.
8. Click Bind.

   Directory Utility displays the authentication and Computer OU dialog.

   

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9. In the Username field, enter the name of an Active Directory administrator or the name of an Active Directory user who has authority to join a computer to the domain.
10. In the Password field, enter the password for the user you specified in step 10.
11. In the Computer OU field, replace the default text with the custom container in which to create the computer object for this Mac OS X computer to use. In the following example, the Active Directory administrator created a new OU specifically for Mac OS X computers and named it “Macs”.
    

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12. Click OK to start the bind process, and then click OK to dismiss the Active Directory services pane. Quit Directory Utility.

Binding to Active Directory with dsconfigad

The dsconfigad command is particularly useful for scripting the process of binding to Active Directory, and it offers a way to bind with custom settings in one step. This command has drawbacks, however: It does not enable the connector, nor does it add the Active Directory node to the search paths. You must also use the defaults and dscl commands to accomplish those tasks.

To bind a computer to Active Directory with dsconfigad, collect the following information for the following dsconfigad options:

• -a—Name of Active Directory computer object to use
• -domain—Fully qualified domain name (FQDN) of Active Directory domain to join
• -u—Name of an Active Directory user who is authorized to add this computer to the domain
• -p—The password for the Active Directory user
• -lu—Name of a local administrator
• -lp—The password for the local administrator

The commands listed in the following exercise enable the Active Directory connector, bind to Active Directory, and add the Active Directory node to the authentication and contacts search paths:

1. Use the defaults command to modify the settings of the file /Library/Preferences/DirectoryService/DirectoryService.plist:

   client17:~cadmin$ sudo defaults write \
   /Library/Preferences/DirectoryService/DirectoryService \
   "Active Directory" Active
   

2. Use dsconfigad to bind to Active Directory:

   client17:~ cadmin$ dsconfigad -a client17 \
   -domain pretendco.com \
   -u Administrator -p ADadminpw \
   -lu cadmin -lp cadmin
   Computer was successfully Added to Active Directory.
   

3. For the authentication search path, use dscl to add “Active Directory/All Domains” to the custom search path (CSPSearchPath), and set the authentication search path to use CSPSearchPath:

   client17:~ cadmin$ sudo dscl /Search -create / SearchPolicy CSPSearchPath
   client17:~ cadmin$ sudo dscl /Search -append / CSPSearchPath \
   "Active Directory/All Domains"
   

4. For the contacts search path, use dscl to add “Active Directory/All Domains” to the custom search path (CSPSearchPath), and set the contacts search path to use CSPSearchPath:

   client17:~ cadmin$ sudo dscl /Search/Contacts -create / SearchPolicy CSPSearchPath
   client17:~ cadmin$ sudo dscl /Search/Contacts -append / CSPSearchPath \
   "Active Directory/All Domains"
   

5. Stop DirectoryService, which automatically starts up again with these new settings:

   client17:~ cadmin$ sudo killall DirectoryService
   

6. Use dscl to confirm that the Active Directory node is in the search paths:

   client17:~ cadmin$ dscl /Search -read / CSPSearchPath SearchPolicy
   CSPSearchPath:
    /Local/Default
    /BSD/local
    Active Directory/All Domains
   SearchPolicy: dsAttrTypeStandard:CSPSearchPath
   client17:~ cadmin$ dscl /Search/Contacts -read / CSPSearchPath SearchPolicy
   CSPSearchPath:
    /Local/Default
    /BSD/local
    Active Directory/All Domains
   SearchPolicy: dsAttrTypeStandard:CSPSearchPath
   

7. Use id to confirm that Open Directory knows about an Active Directory user.

   In this example, the user aduser1 is an Active Directory user object. The -p option makes the output human readable:

   client17:~ cadmin$ id -p aduser1
   uid aduser1
   groups AD\domain users netaccounts everyone com.apple.sharepoint.group.1
   

   If you issue the id command after binding and the result is no such user, wait a few seconds and then try again.

   More Info

   For more options, see the man page for dsconfigad.

Using Configuration Options Available Only with dsconfigad

dsconfigad offers much of the same functionality that Directory Utility offers: You can bind, unbind, set configuration options, and show the status of a bind. In addition, dsconfigad offers some functionality that Directory Utility does not offer, such as the following:

• -packetsign <disable | allow | require>—This supports packet signing options for both SMB and LDAP. SMB signing is required by default on Windows Server 2003 SP1 and later. This caused much frustration with earlier versions of Mac OS X. The default is to allow packet signing.
• -packetencrypt <disable | allow | require>—This supports packet encryption options for both SMB and LDAP. The default is to allow packet encryption.
• -namespace <forest | domain>—The forest option enables a user to log in even if there is another user account with an identical user name in the forest. Be forewarned that if you specify forest, the Active Directory connector calculates each Active Directory user’s local home folder as /Users/DOMAIN\username instead of /Users/username. Toggling the namespace setting after Active Directory users have already logged in can cause confusion, as Active Directory users perceive the contents of their home folder to be missing. The default is domain.
• -passinterval <days>—This specifies how often Mac OS X changes the Active Directory computer object password, measured in days. It is common for Active Directory administrators to use Active Directory tools to look for computers that have not recently changed their passwords. The default is for Mac OS X to change its computer object password every 14 days.

Understanding Mobile Accounts

A mobile account is a local copy of a network user account, with attributes and credentials synchronized at login if the network node is available. A mobile account allows you to log in even when the network directory node is not available. The mobile account concept is not specific to Active Directory, but the Active Directory connector provides an option to enable Mac OS X to create a mobile account when users log in. This enhances the user experience because it caches other information, such as group membership, about Active Directory. Mobile accounts work well when you synchronize the contents of the local home folder with a network home folder, but this is not automatic.

See the section “Exploring the ‘User Experience’ Advanced Options Pane,” earlier in this chapter, for instructions on configuring the Active Directory connector to configure Mac OS X to create mobile accounts. For more information about home folder synchronization, see the section “Managing Mobile User Accounts,” of Apple Training Series: Mac OS X Server Essentials v10.6, or read Chapter 8, “Managing Portable Computers,” of Mac OS X Server User Management Version 10.6 Snow Leopard.

Binding to Active Directory and Open Directory

In any circumstance in which a user account is missing some attributes—for example, because you cannot extend the schema, or you do not have authority to edit the attributes you are interested in—you can always try using the Magic Triangle, in which you use an Open Directory node to supplement data available from the primary node. You learned about this configuration in Chapter 3, in the “Augmenting LDAP Data with Information from an Open Directory Server” section, and it is illustrated in the following figure:

The Magic Triangle configuration lets you apply managed preferences to Open Directory computers and workgroups, and then add Active Directory groups and users to Open Directory workgroups to manage them. See the instructions in Chapter 8, in the section “Preparing Mac OS X Server for the Magic Triangle Configuration.”

Because the Active Directory connector dynamically generates mount records for network home folders, you do not need to provide an additional directory node or mount object to automount an AFP home folder.

Providing Managed Preferences to Active Directory Users

Using Active Directory Group Policy Objects is the traditional method for managing Windows users, groups, and computers, but Mac OS X is not compatible with Group Policy Objects. If you want to apply managed preferences to Mac OS X users, you could do any of the following:

• Augment Active Directory with an Open Directory server, and then make Active Directory users members of Open Directory groups to which you apply managed preferences. See “Using Workgroup Manager to Provide Managed Preferences in the Magic Triangle Configuration,” in Chapter 8, for instructions.
• Use third-party software such as Thursby ADmitMac, Centrify DirectControl, Likewise Enterprise, or other similar products.
• Extend your Active Directory schema to handle Apple-specific object classes and attributes, and then use Workgroup Manager to manage preferences for objects in the Active Directory domain. See the white papers listed in the References section and Appendix B, “Extending Your Active Directory Schema,” available online.

Configuring the Authentication Search Path

If you are connected to multiple directory nodes, and you store managed preferences settings for computers in one node, that is the node that you should configure to be listed before the other nodes in your authentication search path. See Apple knowledge base article TS2528, Mac OS X 10.5: Managed Preferences settings not applied to computer bound to multiple directory services for more information.