You deploy multiple Mailbox servers. Each Mailbox server contains a copy of a mailbox database
named DB1. You need to recommend a solution that allows administrators to remove corrupt
messages that have been replicated before the corrupt messages are applied to each copy of DB1.
What should you recommend?

A.
Modify log truncation.

B.
Enable circular logging.

C.
Implement lagged copies.

D.
Configure shadow redundancy.

Explanation:
Using Replay Lag and Truncation Lag Options
Mailbox database copies support the use of a replay lag time and a truncation lag time, both of
which are configured in minutes. Setting a replay lag time enables you to take a database copy back
to a specific point in time. Setting a truncation lag time enables you to use the logs on a passive
database copy to recover from the loss of log files on the active database copy. Because both of
these features result in the temporary build-up of log files, using either of them will affect your
storage design.
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