Data Protection
Split Mirrors
Split Mirrors
• Split mirrors can also be used to create point-in-time
copies of data
• Split mirrors are maintained using the same process as a
standard RAID mirror set
• The mirroring process can be stopped and the split
mirror volume can then be accessed by another server
Primary RAID
Split
Mirror
All in same array
Some enterprise subsystems also provide a type of mirror called a “split
mirror”.
Unlike a standard mirror, the mirroring process for a split mirror can be
stopped and restarted arbitrarily to split and resynchronize the mirror with the
primary volume.
Like snapshots, this allows users to create point-in-time copies of volumes.
Mirrors can also occur in the host using volume manager. Data would be
written to both volumes during normal operation. Once a point in time copy is
created and the mirror split, a write log is generated for all subsequent writes
which is then used to restore the mirrored image once the mirror is
resynchronized.