Cascade Connection Of Snapshot With Truecopy; Cascade Restrictions With Snapshot P-Vol - Hitachi AMS2100 User Manual

Cascade connection of SnapShot with TrueCopy

Cascade with a P-VOL of SnapShot
SnapShot
Cascade with a V-VOL of SnapShot
SnapShot

Cascade restrictions with SnapShot P-VOL

1-12
Hitachi AMS 2000 Family Copy-on-Write SnapShot User Guide
Volumes of SnapShot can be cascaded with those of TrueCopy as
shown in Figure 1-6. Because the cascade of SnapShot with
TrueCopy lowers the performance, only use it when necessary.
•
Host
Read/W rite
P-VOL
P-VOL
V-VOL
Local array
Host
Read/W rite
P-VOL
P-VOL
V-VOL
Local array
Figure 1-6: Cascade Connection of SnapShot with TrueCopy
When restore using SnapShot is executed, TrueCopy must be in the
Split status. If restore using SnapShot is executed in the
Synchronizing status or Paired status of TrueCopy, the data in the
LUs for P-VOL that are cascaded using TrueCopy on the local side and
the remote side cannot be assured of equality.
SnapShot overview
S-VOL
Cascade Connection
TrueCopy
Remote array
S-VOL
TrueCopy
Cascade Connection
Remote array
P-VOL
SnapShot
V-VOL
P-VOL
SnapShot
V-VOL