HP StorageWorks XP24000 Continuous Access Software User and Reference Guide, v01 (T5278-96002, June 2007)

Group Options
Continuous Access provides the following options for each consistency group: Time Out (Copy Pending)
and Time Out (RCU Ready). These options are selected when you add a group, and can only be modified
if thegroup does notcontain anyP-VOLsinthe MCU.
Time Out (Co py Pending).This group option specifies the maximum delay allowed for Continuous Access
Asynchronous copy operations. The RCU will suspend all S-VOLs in the group when:
• The RCU has not
had
any communications from the MCU within the specified tim e. This s ituation
couldindicateadisaster or failureatthe primarysite.
• The RCU has be en receiving recordsets from the MCU(s), but has not been able to settle a
recordset within the specified time. This situation may indicate that the RCU does not have
enough resou
rces to handle the remote copy and I/O workloads.
Time Out (RCU
Ready). This g roup option specifies the maximum delay allowed for re-establishing
MCU-RCU com
munications following an MCU power-off. During an MCU power-on, the MCU
re-establi
shes communication with all registered RCUs. If the MCU is not able to re-establish
communica
tions with an RCU within the specified time, the MCU suspends all affected Continuous
Access Asynchronous pairs.
Group Operations
Continuous Access Asynchronous provides the following group-based operations to simplify and expedite
disaster/failure recovery procedures:
• Group operations at the MCU:
• Split (pairsplit-r) a ll pairs in a consistency group. See
“Splitting Continuous Access Pairs” on page 114 for a description of the
Suspend Range-G roup pairsplit option.
• Resynchronize (pairresync) a ll split or suspended pairs in a group. See
“Resynchronizing Continuous Access Pairs” on page 117 for a description of the Continuous
Access Resume Range-Group pairresync option.
•
Release (pairsplit-S) all pairs in a group. See “Releasing Continuous Access Pairs” on page 120
for a description of the Delete Range-Group pairrelease option.
• Group operations at the RCU:
• Split (pairsplit-r) a ll pairs in a consistency group. See
“Splitting Continuous Access Pairs” on page 114 for a description of the
Suspend Range-G roup pairsplit option.
• Release (pairsplit-S) all split/suspended pairs in a consistency group except for any
inconsistent pairs. See “ReleasingContinuousAccessPairs” on page 120 for a description of
the Delete Range -C/T pairrelease option.
• Release (p airsplit-S) all pairs in a group regardless of their consistency status. See
“Releasing Continuous Access Pairs” on page 120 for a description of the Delete Range-Group
pairrelease option.
Continuous Access also prov ides the Error level pair option (see “Changin g Pair Options” on page 110),
which is used to trigger automatic suspension of an entire consistency group. When a Continuous Access
Asynchronous pair is suspended due to failure (not user-r equested), this Continuous Access Asynchronous
pair option determines whether all pairs in the same consistency group will also be suspended. If
you selected the Group error level for the Continuous Access pair, all pairs in the same group will be
suspended. If you selected the LU error level, only the affected Continuous Access pair will be suspended.
Note: The Error level pair option is very important for managing Continuous Access Asynchronous groups
and planning for disaster recovery. The Group error level should be selected for all Continuous Access
Asynchronous volumes which are essential to disaster recovery. Suspended Continuous Access S-VOLs
which have the LU error l evel should not be used for disaster recovery.
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HP StorageWorks XP Continuous Access Software Operations