Hitachi AMS2100 User Manual page 4

One LU used for P-VOL on SnapShot and S-VOL on TrueCopy. . . . . . . . 1-13
V-VOLs number of SnapShot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-14
Cascade restrictions with SnapShot V-VOL . . . . . . . . . . . . . . . . . . . . . . . 1-14
Configuration restrictions on the Cascade of TrueCopy with SnapShot . . . . 1-16
Cascade restrictions with SnapShot Data Pool . . . . . . . . . . . . . . . . . . . . . 1-16
Cache memory reconfiguration cautions . . . . . . . . . . . . . . . . . . . . . . . 1-16
Cascade connection of SnapShot with ShadowImage . . . . . . . . . . . . . . . . . 1-19
Cascade connection with P-VOL of ShadowImage . . . . . . . . . . . . . . . . . . 1-22
Restriction when performing restoration . . . . . . . . . . . . . . . . . . . . . . . 1-22
Performance when cascading the P-VOL of SnapShot and ShadowImage1-22
Cascade restrictions with S-VOL of ShadowImage . . . . . . . . . . . . . . . . . . 1-24
Pair Operation Restrictions when Cascading SnapShot with ShadowImage . 1-27
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-29
Simultaneous Cascading Restrictions with ShadowImage P-VOL and S-VOL 1-30
Cascade Restrictions of TrueCopy with ShadowImage and SnapShot . . . . . 1-31
2 Planning and design. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
The plan and design workflow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-2
Assessing business needs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-2
Copy frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-2
Selecting a reasonable time between Snapshots . . . . . . . . . . . . . . . . . .2-3
Establishing how long a copy is held (copy lifespan). . . . . . . . . . . . . . . . . .2-3
Lifespan based on backup requirements . . . . . . . . . . . . . . . . . . . . . . . .2-3
Lifespan based on business uses . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-4
Establishing the number of V-VOLs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-4
Establishing data pool size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-5
Measuring workload data, sizing the data pool. . . . . . . . . . . . . . . . . . . . . .2-5
Rule-of-thumb calculation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-9
Requirements and recommendations for SnapShot Logical Units . . . . . . . . . 2-10
RAID configuration for LUs assigned to SnapShot . . . . . . . . . . . . . . . . . . 2-10
Operating system considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-13
Identifying P-VOL and V-VOL LUs on Windows . . . . . . . . . . . . . . . . . . . . 2-13
LU mapping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-14
Cluster and path switching software . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-14
Microsoft Cluster Server (MSCS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-14
AIX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-14
Veritas Volume Manager (VxVM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-14
Windows 2000 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-14
Windows Server and SnapShot configuration. . . . . . . . . . . . . . . . . . . . . . 2-15
Linux and LVM configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-16
Tru64 UNIX and SnapShot configuration . . . . . . . . . . . . . . . . . . . . . . . . . 2-16
Concurrent use of Cache Partition Manager . . . . . . . . . . . . . . . . . . . . . . . 2-16
VMWare and SnapShot configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-16
Concurrent use of Dynamic Provisioning . . . . . . . . . . . . . . . . . . . . . . . . . 2-18
iv
Hitachi AMS 2000 Family Copy-on-Write SnapShot User Guide
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