10.1 Creating a DFS Management Context

The DFS management context monitors the location of any NSS volume or NCP volume that has a Volume object in a specified O or OU container in the Novell eDirectory tree. Before you can create junctions, you must create at least one DFS management context that contains the volumes you want to target. When you create a DFS management context, you specify one or two servers to host instances of its VLDB service and VLDB. A given server can host only one VLDB. It is the VLDB service and VLDB that allow you to create DFS junctions that point to volumes in the DFS management context.

You can create more than one DFS management context if you have a geographically diverse company. In this way, each geographic area can manage and control the junctions and the VLDB service within its own domain. Whenever you rebuild the VLDB, it searches all services in the context you specify as the DFS management context. If you use DFS for only a small subset of your total servers, the VLDB rebuild is faster if you place only the servers that use DFS in a separate context, then specify the DFS management context at that same level.

After the management context is configured, DFS does not monitor eDirectory for changes to the name or for the existence of the O or OU container. If you change the name of the container or if you delete and replace the container, the DFS management context stops working because its configuration does not match with the information in eDirectory. The VLDB is broken, and junctions that point to volumes in that container are broken. This failure occurs even if you eventually change the name to the original name of the O or OU container. A VLDB repair cannot fix this problem.

WARNING:If you delete or rename the O or OU container that is referenced by a DFS management context, you must delete the existing DFS management context, then create a new DFS management context for that modified container.

If renaming container modifies the name of the nss admin object for a Linux VLDB replica server, perform the steps listed in eDirectory Error 601 When Creating NSS Volume in the OES 11 SP2: NSS File System Administration Guide for Linux before recreating the DFS management context.

To create a DFS management context:

  1. In iManager, select the Distributed File Services role to expand it, then select Create Management Context.

  2. Configure the following parameters:

    Parameter

    Description

    Name

    The distinguished name of the O-level or OU-level container in the eDirectory tree where the management context resides.

    For example, if a tree contains the following O and OU containers, you can specify a DFS management context in any of them:

    • example
    • hr.example
    • mfg.asia.example
    • sales.emea.example

    Replica Site

    The distinguished name of the server where you want to host an instance of the VLDB service for the new management context. A management context can have one or two replica sites. Any supported server within the management context can host a replica of the VLDB service, but the chosen server can host a replica for only one management context.

    The server can be at any level within the specified container but it cannot be in another management context. For example, if a management context exists beneath another context, both function independently. If the server is in the lower-level management context, it cannot host the replica site for the higher-level management context.

    Database Location

    The path to the directory where the VLDB database is stored on the replica site. The default location is the /var/opt/novell/dfs directory.

    IMPORTANT:You should modify the VLDB location only when you are clustering the VLDB service so that the VLDB resides on a shared device.

    The name of the VLDB file itself cannot be specified or modified. The name of the VLDB file is vldb.dat. For information about security issues for the VLDB file, see Section 16.1, VLDB File.

    Run VLDB Service on Server Restart

    Select this check box if you want the VLDB service to begin automatically when the replica server is restarted.

    Deselect this check box if you want to start the VLDB service manually or in a clustered environment.

  3. When you are done, select OK to create the DFS management context and load and activate the VLDB service on the replica servers.

    The create action updates eDirectory. This process can take up to 5 minutes. Do not click again on the page or elsewhere in the browser until the page refreshes with a message that confirms whether the create was successful or not.