You must be prepared for a failover, which
requires manual intervention. You also need to be prepared for a variable step: client redirection.
You can achieve failover and client redirection in a number of different ways, none
of which are particularly graceful.
CHAPTER 6 n MAINTAINING A WARM STANDBY SERVER VIA LOG SHIPPING 164
Step 1: Identify Database State
First, you must decide if the primary server or database is damaged to the point where
failover is even necessary. You may want to avoid failover completely if the time required
to fail over to a standby server is relatively close to the time required to repair the primary
server, and the amount of acceptable data loss on the primary server is equal to or less
than what would be lost by failing over to a standby server.
Note the and condition??”both items must apply. If, for some reason, you could bring
the primary server back online quickly but at the cost of losing a significant amount of
data, you should begin the failover process.
If you decide failover is necessary, take the time to examine what happened to the
primary server and what you might still be able to retrieve from it.
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