In some cases, it??™s wiser to stop entering data than to continue without a mirror.
Failover
You must manually intervene during a failover in High Protection mode. The process is
exactly the same as in High Performance mode. You must first break the mirroring session
with ALTER DATABASE SET PARTNER OFF and then bring the database online with
RESTORE DATABASE <
> WITH RECOVERY. This effectively brings the mirror
online, but the mirroring configuration is gone.
A failover event also means that you now have a stand-alone server handling what
should be mission-critical data (if it isn??™t mission-critical, you should use another mirroring
mode). The real question that you and the business unit must answer is, ???Do we
want to have this server operational???? In many ways, High Protection mode feels like
high-powered log shipping??”that is, its role in life is merely to be a standby database,
used only as a last resort.
There is one key difference between High Protection mode and log shipping or
some other means of having a standby system: synchronous data transfer.
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