On Unix, a user or group is identified by a 32-bit ID number. This is usually sufficient for individual Unix hosts or NIS environments. As more and more Unix hosts are brought into the Active Directory domain, the possibility for conflicting user and group IDs increases. Ideally, each Unix-enabled Active Directory user or group is assigned a unique ID number and this ID is used across all Unix hosts. In practice, this is difficult to achieve because Unix hosts are often managed independently and user accounts are populated organically which leads to many conflicting or duplicated accounts. Safeguard Authentication Services provides several mechanisms to help alleviate this problem.
The Safeguard Authentication Services MMC snapin provides a Unix Account tab for users and groups. The Unix Account dialog checks UID and GID numbers against the Global Catalog to ensure the value is unique in the forest. In addition, Safeguard Authentication Services has updated the default method used to generate unique UID and GID numbers. The generated values are based on a hash of the object GUID of the account. This results in a unique number with the added benefit that the same object always generates the same number.
To avoid conflicting with existing local accounts, Safeguard Authentication Services provides UID and GID ranges that you can configure in Control Center. The Safeguard Authentication Services management tools do not allow you to set the UID or GID on an Active Directory object to a value that is outside of the configured range.
Using Management Console for Unix, you can gather all of the disparate local account information into one console to consolidate and map local users to the appropriate Active Directory account without disrupting normal operation of the Unix hosts.
Once you have mapped all of the local accounts to Unix-enabled Active Directory users, you can use the Ownership Alignment Tool (OAT) to take the final step of adjusting local file permissions and eliminating the local user (and group) accounts. See Managing local file permissions for more information about using OAT.
The Safeguard Authentication Services LAM module has the ability to service a number of user attributes beyond the standard Unix identity attributes (UID, GID, Shell, and so on). For example, you can store user-specific ulimit attributes, such as fsize, core, or cpu. There are many other attributes you can service with the Safeguard Authentication Services LAM module.
To store all of these attributes in an LDAP directory, IBM provides a user object schema extension. Safeguard Authentication Services does not require this schema extension to service these extended attributes. Instead, the Safeguard Authentication Services LAM module stores this extended attribute data in a local database. In this way, the Safeguard Authentication Services module is a hybrid module; it serves core identity information (UID) from Active Directory, while storing and serving these extended user attributes locally. Since extended attributes are stored locally on each AIX server, you must make extended attribute changes for user accounts on every AIX server.
Use the chuser command to set an extended attribute on a Safeguard Authentication Services user, as follows:
bash$ chuser fsize=3000000 user1
You can set any number of attributes in this fashion.
After setting the value, you can view it using the lsuser command:
bash$ lsuser user1
user1 id=5000 pgrp=jdgroup home=/home/user1 shell=/bin/bash gecos= registry=VAS fsize=3000000
You can set a large number of attributes this way; however, you can not set attributes that have either a static value returned by the Safeguard Authentication Services LAM module or a read-only value served out of Active Directory.
These are the attributes you can not set through the Safeguard Authentication Services LAM module (chuser).
Table 15: AIX extended attributes
| SYSTEM |
| account_locked |
| auth1 |
| auth2 |
| gecos |
| groups |
| groupsids |
| home |
| id |
| pgid |
| pgrp |
| pwdwarntime |
| registry |
| shell |
| unsuccessful_login_count |
| logintimes |
| expires |
| maxage |
| minage |
Use the rmuser command to remove all of the extended attributes from an Safeguard Authentication Services user. The rmuser command usually deletes a user, but when used on an Safeguard Authentication Services user, it only removes attributes stored locally on the AIX server. It never modifies anything in Active Directory.
Notice in the following example that you can still list the user. The only thing missing is the fsize attribute that was just set using chuser.
bash$ rmuser user1
bash$ lsuser user1
user1 id=5000 pgrp=jdgroup home=/home/user1 shell=/bin/bash gecos= registry=VAS
The Unix Account Import Wizard is a versatile tool that helps migrate Unix account information to Active Directory. It is especially well-suited to small, one-shot import tasks, such as importing all the local user accounts from a specific Unix host. The Unix Account Import Wizard can import Unix data as new user and group objects, or use the data to Unix-enable existing users and groups. In Unix Personality Mode, you can use account information to create and link personality objects.
The Unix Account Import Wizard provides several different ways to import Unix account data into Active Directory. You can import Unix account information from various sources, such as local files, remote Unix hosts, and NIS servers. Once the wizard has imported the source data, it uses customizable rules to match the source accounts with existing accounts in Active Directory or uses the information to create new accounts in Active Directory.
The Import Source Selection page allows you to select the source of your Unix account information by clicking on an item in the list. You can only import from a single source, but you can run the Account Importer several times to capture data from multiple sources. Options include:
-
Local Files
Import Unix account information from text files in /etc/passwd format stored on the local host.
You can easily migrate local users to Active Directory by exporting a file from the Master /etc/passwd List report accessible from management console's Reports page, then importing it into the Unix Account Import Wizard accessible from the Safeguard Authentication Services Control CenterTools navigation link.
NOTE: By default, Management Console for Unix creates the Master_etc_passwdList .csv file in the Application Data directory:
NOTE: You can also use vastool utilities from a Unix server command line, such as vastool load, to assist you in migrating local users to Active Directory. See the vastool man page located in the docs directory of the installation media.
-
NIS Server
Import Unix account information directly from the passwd and group maps of an active NIS server.
-
Remote Unix Host
Import Unix account information directly from /etc/passwd or /etc/group files stored on a remote Unix host. This option uses SSH to retrieve the remote data so you must have an SSH login on the remote Unix host.
-
Existing Unlinked Unix Personalities
Use this option to link orphaned or newly created Unix personalities with Active Directory users and groups. This option does not create new objects in Active Directory. It provides a way to quickly find and link Unix personalities using matching rules. This option is only available when the Unix Account Import Wizard is launched from Active Directory Users and Computers in the context of a Primary UPM container. (Right click on a UPM container and select All Tasks | Unix Tasks | Unix Account Import Wizard.)
-
Saved Import Session
Use this option to resume an import session that was saved previously.
-
Existing Active Directory objects
Use this option to create Unix personality objects based on existing Active Directory users and groups. This is helpful when creating new personality containers that are pre-populated with a set of personality objects linked to existing users and groups.
