HP StorageWorks XP Remote Web Console Software - Manual (Page 30)

30 Using Snapshot XP
You can usually use the pools and Snapshot XP pairs you used before switching off the power.
However, since the array checks the status of pools and pool volumes, if pool volumes are blocked at
that time, the pool is blocked and the status of Snapshot XP pairs changes to PSUE. When this occurs,
you must recover the pools after switching on the power. For more information, see ” Recovering
blocked pools ” on page 68.
• If information in shared memory is lost after switching off the power supply
The array has a battery to maintain information in shared memory. However, when a certain time
period elapses after the breaker is turned off, the battery dies and information in shared memory is
lost. If information in shared memory is lost after switching off the power supply, information about
pools and Snapshot XP pairs is erased. Therefore, you must create pools and pairs again after
switching on the power.
For more information about the amount of time before information in shared memory is lost when the
breaker is turned off, contact your HP account support representative.
Replacing the microprogram offline
Replacing the microprogram is usually performed online, but in some cases, such as when the shared
memory configuration must be changed, replacing the microprogram is performed offline. If you replace
the microprogram offline, pool information or Snapshot XP pair information in shared memory is lost.
Therefore, you must create pools and pairs again after replacing the microprogram.
Combining Snapshot XP with other software products
You can create Snapshot XP pairs by sharing volumes with other products, such as Business Copy XP or
Continuous Access XP. In addition, you can create Snapshot XP pairs using volumes to which LUN
Security XP Extension or RAID Manager XP have assigned attributes. Table 8 shows whether or not
Snapshot XP pairs can share volumes with other software products.
Table 8 Volume sharing with other software products
Volumes of other software products Snapshot XP pair P-VOL Snapshot XP pair S-VOL
Business Copy XP pair P-VOL OK 1
1. A Business Copy XP and Snapshot XP pair cannot have the same mirror unit (MU) number. For example, if the Business Copy
XP pair’s MU number is 0, you cannot create a Snapshot XP pair whose MU number is 0 and whose P-VOL is also used as a
Business Copy XP P-VOL. Also, if the Snapshot XP pair’s MU number is 1, you cannot create a Business Copy XP pair whose MU
number is 1 and whose P-VOL is also used as a Snapshot XP P-VOL.
No
Business Copy XP pair S-VOL OK 1 No
Continuous Access XP pair P-VOL OK No
Continuous Access XP pair S-VOL OK No
Continuous Access XP Journal pair P-VOL OK No
Continuous Access XP Journal pair S-VOL OK No
Auto LUN XP source volume OK NO
Auto LUN XP target volume No No
Read Only volume OK OK
Protect volume OK OK
S-VOL Disable volume OK OK
Volume with VMA No No
Volume with extents No No
Zero Read Capacity volume OK OK
Invisible volume OK OK