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

Storage Mirroring Guidelines for networking and failover application notes 19
Diagnosing common issues
Issue Clients receive “The network path was not found” when attempting to access the failed-over
source.
Diagnosis This error is returned if the source name is resolved to an IP address or TCP/IP port that is not
responding.
Possible Causes The client or target is pre-Windows 2000 and the name resolution server (WINS or DNS)
used by the client is not being updated to associate the source name with the target's
primary IP address. Failure to update the WINS server is by far the most common cause of
this issue.
The source's IP address or name was not added to the target at failover.
The client is pre-Windows 2000 and NetBIOS over TCP/IP (NetBT) is disabled on the target
network adapter.
Primary
Troubleshooting
Confirm that the failover monitor is configured to fail over the source's name.
Confirm that the failover monitor is configured with failover scripts to update all WINS and
DNS servers used by all clients to associate the source name with the target's primary IP
address.
Confirm that the Storage Mirroring service account has the necessary permissions to
complete the failover script commands that make the changes to the WINS and DNS
servers.
If clients are pre-Windows 2000, confirm that NetBT is enabled on the appropriate target
network adapter.
Advanced
Troubleshooting
Run
nbtstat -n on the target to confirm that the source's name was failed over. If the
source name does not appear in the NetBIOS local name table, check the failover monitor
configuration to ensure that it is configured to fail over the source name. Check the Windows
application log and Storage Mirroring log on the target to confirm that failover occurred.
Check the WINS records associated with the source name on all WINS servers used by
clients. Check the following items if the WINS entries do not associate the source name to
the target's primary IP address.
Confirm that failover scripts have been configured to update the WINS servers.
Confirm that the Storage Mirroring service account has the appropriate permissions to
successfully complete the commands to update the WINS servers. This can be done by
logging on to the target server with the Storage Mirroring service account, running WINSCL
or NETSH interactively, and entering the commands manually. This can also be done by
redirecting the output of the failover script to a text file to review the script results.
Confirm that the failover scripts are correct by running WINSCL or NETSH interactively and
entering the commands manually. This can also be done by redirecting the output of the
failover script to a text file to review the script results.
Run
IPCONFIG /ALL on the target to confirm that the source's IP address was added to the
correct adapter.
Issue Windows 2000 and later clients receive “login failure, the target account name is incorrect”
or “access denied” when attempting to access a failed-over source.
Diagnosis Service Principal Names are properties of Active Directory computer accounts. When clients
make a connection to a server, they query Active Directory to find the HOST SPNs for the
server name used in the connection request. If a HOST SPN exists, the connection will fail if
the server receiving the connection request is not the computer associated with the computer
account that owns the SPN.