What is meant by Redo Log file mirroring ? How it can be achieved?

What is meant by Redo Log file mirroring ? How it can be achieved?
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1 Answer

Answer :

Process of having a copy of redo log files is called mirroring. This can
be achieved by creating group of log files together, so that LGWR will
automatically writes them to all the members of the current on-line
redo log group. If any one group fails then database automatically
switch over to next group. It degrades performance.
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