HP Storage Mirroring V5.1 Software - Manual (Page 113)

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Configuration requirements
Storage Mirroring failover can be implemented with very little configuration necessary in small or
simple networks, but additional configuration may be required in large or complex environments.
Because an infinite number of network configurations and environments exist, it is difficult to identify
all of the possible configuration steps required for failover. You need to carefully review the
configuration requirements, including those for all environments and those sections specific to your
environment.
Review the following configuration sections.

All environments on page 17-2

Domain controllers on page 17-2

Routers on page 17-2

Cluster configurations on page 17-3

WINS on page 17-3

DNS on page 17-5

Macintosh shares on page 17-9

NFS shares on page 17-10
All environments
All environments, regardless of the configuration, should meet the following requirements.

The source and target should be similarly configured (operating system, applications, service
packs, patches, and so on) so that the applications and services running on the source are
available on the target after failover.

Required applications should be preinstalled on the target and left idle so they do not open or
modify replicated files. Failover scripts will start and stop required applications.
Domain controllers
Failover of domain controllers is dependent on the Storage Mirroring feature you are using. If you
want to failover a domain controller, including the roles of the domain controller, you must use
Full-Server Failover or Virtual Recovery Assistant. See the appropriate User’s Guide for those features
for details on domain controller failover.
With standard Storage Mirroring, you can failover a domain controller, but the roles of the domain
controller are not included. The server will be a member server after failover. If you want to failover
a domain controller using standard Storage Mirroring, keep in mind that unavailability of some of the
FSMO roles (Flexible Single Master Operation) can cause immediate issues such as the inability to
extend the Active Directory schema or to add a domain to a forest. Additionally, if your source is a
global catalog server, you should have other global catalog servers throughout the network to ensure
that the failure of the source will not impact users
Routers
Depending on the type of router you are using, failover may or may not be advisable. For example,
failover across a NAT router is not advisable, because you would only be able to monitor the IP
address of the NAT, not the IP address of the source. In that case, failover would occur when the NAT
router was unavailable, not when the source was unavailable.
Failover across a firewall can be performed. By default, a destination host unreachable message will
trigger failover. If you do not desire this functionality, it can be disabled using the
FailoverOnRouteFailure server setting. See the server settings in the Scripting Guide for more
information on this option.