Restoring eDirectory on NT after a Hardware Failure
(Last modified: 18Jul2002)
This document (10072461) is provided subject to the disclaimer at the end of this document.
Restoring eDirectory on NT after a Hardware Failure
Instructions in the following section give information you need to know about eDirectory on a specific server when you have a hardware failure. For information on backing up and restoring an entire eDirectory tree on Windows NT, refer to Using Backup and Restore Services on Windows NT. In a multiple-server environment, one server can go down while the rest of the servers in its replica list remain intact. If the hard disk containing the eDirectory files on one NT server becomes damaged, it is equivalent to removing eDirectory from the server. To restore eDirectory to a single server, you will need to complete the following procedures:
-Retrieving Server-Specific Information Files
-Cleaning Up the Replica Ring
-Installing the New Server
-Adding the New Server to Previously Defined Replica Rings
-Verifying Successful eDirectory Restore
Step-by-step instructions are as follows:
Retrieving Server-Specific Information Files
The following procedure assumes you have a current backup of the server-specific information for the failed server.
IMPORTANT: If you do not have a backup for the failed server, you will need to remove the server object from the tree and restore eDirectory as explained in Novell Technical Information Document #10011467. From your backup host server, run SMS and restore local server information files from a tape backup. The local server information files should be created and backed up periodically as part of your disaster recovery plan. These files are created in the novell\nds\DIBfiles directory when you load INSTALL.DLM from the NDS Services console and select the Backup Local Server Information option. The following files should be restored:
$SVNDS.BAK contains server-specific NDS information that allows trustee assignments and other NetWare information to be preserved.
DSBACKUP.LOG contains a list of replicas, their types, and other servers that participated in the failed server's replica ring.
Make these files easily accessible for use during the remaining process. For complete information on using SMS, see the Storage Management Services Administration Guide.
Cleaning Up the Replica Ring
This procedure explains how to Reassign master replicas: If the failed server holds a master replica of any partition, you will use DSREPAIR to designate a new master replica on a different server in the replica list. Remove replica list references to the failed server: Each server participating in replica rings that included the failed server must be told that the failed server is no longer available. Use the information contained in the DSBACKUP.LOG file to determine which replicas were stored on the failed server. At the NDS Services console, select DSREPAIR.DLM and enter -a in the Command Line field, then choose Start.
WARNING: If used incorrectly, using DSREPAIR with the -a option can cause damage to your tree. For more information on these options, refer to the Technical Support Web site Solution 2938493. In the DSREPAIR browser window, expand the Partitions list > select the replica you want to designate as the master > click Partitions > click Designate This Server as the New Master Replica. The replica ring now has a new Master Replica. All replicas participating in the ring will be told that there is a new master. In the DSREPAIR browser window, expand the Partitions list > select the replica from which you want to remove the server > select the failed server > click Partitions > click Replica Ring > click Remove Server from Ring. Exit DSREPAIR. All servers participating in that replica ring will be notified of replica ring updates. Repeat this procedure as applicable on one server for each replica ring that the failed server participated in. Force synchronization of all replicas in DSRepair. Choose Replica Rings > Send all objects to every replica in the ring.
Installing the New Server
This procedure covers installing the Windows Operating System and installing eDirectory. Install the new hard disk or server hardware. Follow any instructions provided by the manufacturer to verify that the server's hard disks are working. The new hard disk should have the same (or larger) storage capacity as the drive it replaces. Use the local server information files to verify configuration information. Install the Windows 2000 or NT operating system. Install eDirectory on NT on the new server. See Installing eDirectory for Windows NT/2000 Server. When prompted to enter a tree name, enter a new tree name so the server will install into its own temporary tree. From the NDS Services console, select INSTALL.DLM > click Start > click Remove Directory Services > click Finish. Enter the administrator name and password > click OK and follow the prompts. eDirectory is removed. From the NDS Services console select INSTALL.DLM > click Restore Local Server Information after a Hardware Failure > click Next. Specify the path to the $SVNDS.BAK file > click OK. eDirectory is restored at this time using the information in $SVNDS.BAK, but you still need to prepare the directory for integration and re-establish the partitions and replicas. Prepare the restored directory for integration into the original tree by executing the following DSREPAIR commands from the newly restored server in the order specified:
WARNING: The following DSREPAIR commands should only be used in this procedure and should be executed in the order given. DO NOT use these commands for general DSREPAIR operations.
DSREPAIR -si (Repairs replica numbers on partition objects)
Choose Repair > Local database repair
Choose Servers > Repair all network addresses
Choose Schema >Reset local schema
This is a clean up process. It's ok to see error messages displayed during the clean up.
Use DSTRACE to verify that the schema has synchronized fully. From the NDS Services console, select dstrace > click Start. Choose Edit > Options and mark Schema and sync incoming, then choose OK. Watch for the message "All processed = YES." Once the schema is synchronized, you are ready to re-establish replicas.
Adding the New Server to Previously Defined Replica Rings
This process ensures replication on the new server will be at the same level as it was on the failed server. View the contents of DSBACKUP.LOG. It contains a copy of the replica list that resided on the server at the time the backup was made. Re-establish replicas on the failed server using ConsoleOne. In the left pane, right-click the root container of the partition that you want to replicate > click Views > click Partition and Replica View. On the toolbar, click Add Replica. Next to the Server Name field, click the browse button > select the server you just restored > click OK. Select the type of replica you want > click OK. If the failed server had master replicas, you can designate that same set of replicas as master replicas. For information on using ConsoleOne, see the online help.
Verifying Successful eDirectory Restore
Use ConsoleOne to verify that the server's replica states are On
Right-click the server in the left pane > click Views > Partition and Replica View..
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- Document ID:
- Solution ID: NOVL80777
- Creation Date: 10Jul2002
- Modified Date: 18Jul2002
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