Contemporary CDP Appliance Vs StorTrends iTX Installation CDP
In contemporary CDP appliances, the write I/Os are replicated outside the appliance
using some sort of data-tapping agents. This mirrored I/O is then (1) staged in a buffer in
the appliance. The old data is (2) read from the recovery volume, time-stamped and (3)
journaled out into a "undo" journal device. Subsequent to this, the staged I/O is (4)
written on to the recovery volume and finally the (5) operation is completed to the host.
During Review or Rollback, a Time image volume is created by replaying the undo
journal from the current time to the selected time or event.
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StorTrends/ManageTrends (version 2.7) Web Interface User's Guide for the StorTrends 2200 Storage Appliance