What is advantage of having disk shadowing/ Mirroring ?

What is advantage of having disk shadowing/ Mirroring ?
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1 Answer

Answer :

Shadow set of disks save as a backup in the event of disk failure. In
most Operating System if any disk failure occurs it automatically
switchover to place of failed disk. Improved performance because most
OS support volume shadowing can direct file I/O request to use the
shadow set of files instead of the main set of files. This reduces I/O
load on the main set of disks.
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