HP StorageWorks Continuous Access EVA Administrator Guide (T3687-96043, December 2005)

Table 5 Replication m anager display icons
Resource
Symbol
Description
Array
Indicates the array is in an
abnormal state and requires
attention.
Virtual disks
Indicates a catastrophic failure
and requires immediate action.
DR groups
Red indicates a failure; yellow
indicatestheDRgroupisina
degraded state. Either condition
requires immediate attention.
Disk group hardware failure on the source array
Possible scenario: A hardwar e failure on a source array causes a disk gr oup to become inoperative .
This can be caused by the loss of enough disks to lose redundancy within the disk group and affects all
Vraid types present on the disk group.
Action summar y: If you plan to recover using data on the destination array, then fail over the destination
array. Delete DR groups and virtual disks on the failed array. Repair the failed disk group. Re-crea te DR
groups, virtual disks, and host presentations. If the failed source array was logging at the time of the
hardware failure, you must recover with data at the destination site or from a backup.
There are t
wo ways to recover from a disk group hardware failure on the source array:
• If data replication was occurri ng normally when the source disk group b ecame inoperative, the
data at the destination array is current and crash consistent. Fail over on the destination a rray,
delete DR g
roups, repair the inoperative disk group, and re-create the DR groups. Copy data
from the d
estination to the repaired source.
• If your disk group becomes inoperative when the DR groups are logging (for example, your
DR groups were suspended, or the interswitch links are down), the data is stale but still crash
consistent on the destination array (unless a full copy was in prog ress). Stale data is older
data that is not as current as what exists on the other array. If you prefer to use stale data for
recover
y, the steps are the same as if replication was occurring normally. However, if you prefer
to cont
inue from a point-in-time, copy and then repair the inoperative disk group, and data is
restor
ed from a backup or full copy.
NOTE:
When you delete DR groups to recover from a disk group hardware failure , you lose the disaster
tolerance of your data.
Procedure:
P erform this procedure when a disk group hardware failure occurs on the source array and the data on
the destination array is current.
1. Using HP Command View EVA, navigate to each DR group on the destination array and fail over
(see Unplanned failover).
2. On the failed (previous source) array, navigate to the failed disk group.
A list of failed virtual disks and DR groups is displayed.
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Failover and recovery