HP StorageWorks Storage Mirroring Full-Server Failover Evaluation Guide (T2558-96331, April 2009)

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Evaluating Full-Server
Failover
Full-Server Failover configuration consists of various tasks for establishing server protection,
simualating a failure, and performing failover. The evaluation includes the following tasks.
1. Finding a compatible target on page 4-1
2. Establishing server protection on page 4-3
3. Monitoring failover on page 4-5
4. Causing and verifying replication on page 4-6
5. Simulating a failure on page 4-7
6. Starting failover on page 4-7
Finding a compatible target
The target you select must be suitable for becoming the source, in the event the source fails.
Full-Server Failover will validate the target and identify any incompatibilities. Errors will disqualify the
target as a suitable server. To find a compatible target, check the table below for each of the
requirements.
Target Compatibility
Requirement Configuration
Operating system
version
The source and the target must have the same operating system. For
example, you cannot have Windows 2003 on the source and Windows 2008
on the target. The two servers do not have to have the same level of service
pack or hotfix.
Domain The domain of the source should be the same as the domain of the target.
Server role The source and target cannot both be domain controllers. Only one or the
other can be a domain controller. Ideally, the target should not be a domain
controller or host any functionality (file server, application server, and so on)
because the functionality will be removed when failover occurs.
If your source is a domain controller, it will start in a non-authoritative restore
mode after failover. This means that if the source was communicating with
other domain controllers before failover, it will require one of those domain
controllers to be reachable after failover so it can request updates. If this
communication is not available, the domain controller will not function after
failover. If the source is the only domain controller, this is not an issue.
Architecture The source and the target must have the same architecture. For example, you
cannot failover a 32-bit server to a 64-bit server.
Processors There are no limits on the number or speed of the processors, but the source
and the target should have at least the same number of processors. If the
target has fewer processors or slower speeds than the source, there will be
performance impacts for the users after failover.
Memory The target memory should be within 25% (plus or minus) of the source. If the
target has much less memory than the source, there will be performance
impacts for the users after failover.