HP StorageWorks Storage Mirroring application notes Guidelines for networking and failover (T2558-96063, February 2008)

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Possible Causes SPNs are not getting changed at failover.
Clients are using a domain controller that has not yet received the changes to the SPNs.
Primary
Troubleshooting
Confirm that the failover monitor is configured to fail over and fail back the Active Directory
host name.
If NSISPN is being used in failover scripts, confirm that it is version 1.1 or later.
Advanced
Troubleshooting
After failover, run “
NSISPN -L [source]” from the target and save the output for review.
If the
HOST/SOURCE and/or HOST/SOURCE.domain.com SPNs are present, confirm the
following:
The “failover hostname” and “failback hostname” options are enabled on the failover
monitor.
If Storage Mirroring 4.2 Service Pack 1 or later is not in use and the source's Active
Directory computer account is not in the Computers container, use the NSISPN (version 1.1
or later) utility in the failover scripts to make the necessary SPN changes.
Ensure that the “Write servicePrincipalName” permission (at a minimum) has been assigned
to the appropriate account, as explained in Active Directory and Service Principal Names
on page 12.
If the HOST SPNs are not present, run “
NSISPN -L [source]” from the client. If the SPNs
are different from those reported when running the same command from the target, then the
issue is most likely due to the lag in propagation of the SPN changes to other domain
controllers. This is most likely to occur when there are multiple sites in AD and the client is in
a different site. This can be resolved by forcing replication after failover with the Replication
Diagnostics Tool (
Repadmin.exe) in the Windows Support Tools. The Replication
Diagnostics Tool can be used in the failover script to ensure that changes to the SPNs are
replicated to other domain controllers immediately.
Issue Clients cannot print after failover occurs.
Diagnosis The Windows NT 4.0 and Windows 2000 print spooler binds to the name that is specified
as the ActiveComputerName, and requests to the spooler that use a different name will fail.
The HP ChngName utility must be used in the failover script to change the
ActiveComputerName. See the Guidelines for Using Storage Mirroring with Windows Print
Servers application note, available from the Application Notes section of the HP support
web site (<code text>http://support.doubletake.com), for details on using the ChngName
utility for print server failover.
Possible Causes 1. The ChngName utility was not used correctly.
2. A name resolution or SPN issue is causing attempted client connections to fail.
3. Failover for more than one source has occurred, and printing is only working for the last
source that was failed over. If failover has occurred for more than one source, printing
will only be available to the clients that were using the last source to failover. The print
spooler will only respond to requests that use the ActiveComputerName that was in
place when the print spooler service was last started.
Primary
Troubleshooting
1. Confirm that the ChngName utility was used correctly in the failover scripts.
ChngName
/t
must not be run in the failover script for Windows 2000 print servers.
2. Try to view a share on the target using the source's name. If clients are getting “Network
path not found,” or other error messages, see the previous sections to resolve name
resolution or SPN issues.
3. Run the failover script manually to ensure that all commands complete correctly and
resolve any failures.