Troubleshooting VSS backup and restore operations

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If you encounter a problem during VSS backup and restore processing, attempt to reproduce the problem in your environment.

Before you begin

If a VSS backup fails, verify that sufficient disk space is available to store the snapshot.

Procedure

  1. Try the operation that failed again.
  2. Restart the IBM Storage Protect™ services, including the TSM Client Acceptor and the TSM Remote Client Agent.
  3. If the problem still exists, close other applications, especially those applications that interact with Exchange, for example, antivirus applications. Retry the operation that failed.
  4. If the problem persists, look for information in the event logs: tdpexc.log and dsmerror.log.
    You can also review the messages in the Windows™ event log. Log entries might exist to help you identify the VSS event that triggers the issue.
  5. If you do not find a resolution to the problem in the log files, complete the following steps:
    1. Shut down the Exchange server or the computer.
    2. Restart the Exchange server or the computer.
    3. Run the operation that failed.

Failovers from VSS instant restore processing to VSS fast restore processing

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If an error occurs early in a VSS instant restore operation, the error might cause the system to fail over to VSS fast restore processing. However, if an errors occurs later in the instant restore operation, instant restore processing might fail without failing over to fast restore processing.

About this task

Errors in VSS instant restore operations might occur, for example, if the volume where the restored database is stored is used by another process.

Procedure

Check the error message in the dsmerror.log file.

Troubleshooting VSS limitations with IBM SAN Volume Controller and IBM Storwize V7000

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When you run IBM Storage Protect Snapshot for Exchange Server VSS backups (non-offloaded) to a backup destination of IBM Storage Protect server, the IBM® SAN Volume Controller or IBM Storwize® V7000 LUNs can sometimes remain mapped to the Windows host even though the backup is complete.

Procedure

Use a backup destination other than IBM Storage Protect server (BOTH or LOCAL).

Results

When you run two IBM Storage Protect Snapshot for Exchange Server VSS backups and if the volumes are large, or the background copy rate is set to a low number, or both conditions occur, the second VSS backup might be presented to be in a hang state. Typically, the Exchange Server data is on IBM SAN Volume Controller or IBM Storwize V7000 disks. However, the second backup is waiting for the IBM SAN Volume Controller or IBM Storwize V7000 background copy of the first backup to complete before proceeding. IBM SAN Volume Controller or IBM Storwize V7000 does not allow two background copies of the same volume to occur at the same time. You might not know that the second backup is waiting for the first background copy to complete.

You might also see timeout errors if the previous IBM SAN Volume Controller or IBM Storwize V7000 background copy takes too long.

What to do next

To resolve timeout issues, schedule VSS backups so that enough time elapses between backups, or increase the copy rate of the IBM SAN Volume Controller or IBM Storwize V7000 background copy.

Troubleshooting VSS limitations with IBM N-series and NetAppFAS series

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If you plan to run VSS backups with backup destination set to LOCAL, understand the limitations in the VSS Provider for NetApp FAS series and IBM N-series, and in SnapDrive 4.2 and earlier versions, that affect the way in which you can run your VSS backup operations. You must configure your environment correctly to avoid snapshot deletions, backup failure, and out-of-space conditions on the production volumes.

Before you begin

  • Ensure that a NAS file server LUN that is used by Exchange Server databases is fully dedicated to the database. Exchange Server databases cannot share LUNs.
  • Ensure that a NAS filer LUN that is used by Exchange Server databases is the only LUN on the filer volume. For example, if the Exchange Server uses four LUNs, four corresponding filer volumes must exist, where each volume contains one LUN.
  • If the NetApp volume type is Traditional, ensure that VSS backups with backup destination set to LOCAL are bound to a management class that has verExists=1. This setting is not required if flexible volumes are used.
  • Ensure that VSS backups with backup destination set to LOCAL are either a full or copy backup. You cannot mix local backups of type FULL and COPY.
  • Ensure that VSS backups with backup destination set to TSM are a full or copy backup. There are no restrictions on IBM Storage Protect backups.
  • When you run VSS backups, ensure that previous backups finish completely before you start a new backup. To avoid issues on Exchange Server, the VSS service, and, the NAS filer, avoid backup overlaps.

About this task

The following backup procedure is an example that shows how to optimally run VSS backups by using both IBM Storage Protect and local backup destinations. The following assumptions apply to this example backup procedure:
  • Stated configuration requirements are in place.
  • Daily VSS full backups to a local destination occurs every four hours - 12 a.m., 4 a.m., 8 a.m., 12 p.m., 4 p.m., 8 p.m.
  • The VSS backup to IBM Storage Protect takes one hour to complete.
  • The VSS backup to a local destination takes five minutes to complete.

Procedure

Set your daily VSS full back schedule to run in one of the following ways:
  • Run daily VSS full backups to a local destination every four hours - 12 a.m., 4 a.m., 8 a.m., 12 p.m., 4 p.m., 8 p.m.
  • Run daily VSS full backups to IBM Storage Protect storage by one of the following two methods:
    • Set backupdestination to BOTH to run at 12 a.m. Because this setting runs a 12 a.m. backup to a local destination, do not separately schedule a 12 a.m. backup to a local destination.
    • Set full offloaded-backup to run at 1 a.m. No VSS local backup is available to restore VSS backups between 1 a.m. and 4 a.m., when the next VSS backup to a local destination occurs.
  • Set weekly VSS full backups to run to IBM Storage Protect, as an offloaded backup, at 5 a.m.