HP XP RAID Manager Software - Manual (Page 20)

Split operation. When I/O does not occur, the storage system timer performs the Split
operation.
◦ If the split operation fails, the status all volumes in the consistency group remains the same
as before the At-Time Split operation.
•
If the consistency group contains a pair whose status cannot be changed, the pairsplit
command can terminate abnormally (with error code EX-EWSTOT (Timeout)). The following
are possible reasons:
◦ The SS P-VOL is also used as an Cnt Ac-J S-VOL and the Cnt Ac-J journal capacity is
insufficient.
◦ The SS license is invalid.
◦ An SS pair volume is blocked.
◦ The SS pair has a status that does not allow you to perform the pairsplit operation.
For more information about SS pair status, see “Statuses required for RAID Manager pair
operations” (page 67) .
◦ The SS pair has a status that does not allow Cnt Ac-J to run the pairsplit command.
Pair inclusion in At-Time Split operations workflow
Use the following process to include pairs in an At-Time Split operation:
1. Review the requirements for consistency groups in “Consistency group system requirements”
(page 11) .
2. Place the pairs in a consistency group. Specify only one consistency group for a group defined
in the RAID Manager configuration file.
NOTE: Performing the pairsplit operation when the pairs are placed in a consistency group
does not guarantee the acquired snapshot data to be the P-VOL data.
To guarantee that the acquired snapshot data is the P-VOL data, include pairs that do not
share the same P-VOL in the consistency group.
To avoid a pairsplit operation failure, include only pairs that are in consistency groups
in a group (not a consistency group) that you have defined in the RAID Manager configuration
file. When creating a pair using a group that you defined in the RAID Manager configuration
file, if another pair in the group is part of a consistency group, place the pair you are creating
in the same consistency group. If you want to specify multiple consistency groups, define a
group for each consistency group.
To avoid a command rejection and a generating a consistency group number that does not
include the SS pair, create a pair for an At-Time Split operation when the host server is running.
If the host server is down, create the pair using the consistency number. In RWC, use the
Consistency Groups tab in the Local Replications window.
For more information about creating pairs using the paircreate command, see “Creating
pairs in a consistency group” (page 109) .
Consistency maintenance workflow when sharing SS P-VOLs with Cnt Ac-J or Cnt
Ac-S volumes
Use the following process to share SS P-VOLs with Cnt Ac-J or Cnt Ac-S S-VOLs within a storage
system and to maintain consistency:
20 Business Copy/Snapshot planning and design