Administrator Guide

Table 11. Consistency group field descriptions (continued)
Property Description
● winner - The cluster specified by cluster-name will be declared the winner if
an inter-cluster link outage lasts more than the number of seconds specified
by delay.
storage-at-clusters
The cluster where the physical storage associated with a consistency group is
located.
● Modifiable using the set command. If cluster names are cluster-1 and
cluster-2 valid values are:
○ cluster-1 - Storage associated with this consistency group is located
only at cluster-1.
○ cluster-2 - Storage associated with this consistency group is located
only at cluster-2.
○ cluster-1,cluster-2 - Storage associated with this consistency
group is located at both cluster-1 and cluster-2.
● When modified, the new value cannot be incompatible with the volumes that
are already in the consistency group. Change storage-at-clusters only
when the consistency group has no member volumes.
visibility
Lists the clusters at which this consistency group is visible.
● Modifiable using the set command. If cluster names are cluster-1 and
cluster-2 valid values are:
○ cluster-1 - This consistency group is visible only at cluster-1.
○ cluster-2 - This consistency group is visible only at cluster-2.
○ cluster-1,cluster-2 - This consistency group is visible at both
cluster-1 and cluster-2.
● Changing this property changes where the consistency group is visible, and
may cause contexts to appear or disappear in the context tree.
virtual-volume
Lists the virtual volumes that are members of the consistency group. Modifiable
using the following commands:
● consistency-group add-virtual-volumes - Add one or more virtual
volumes to a consistency group.
● consistency-group remove-virtual-volumes - Remove one or
more virtual volumes from a consistency group.
Advanced properties
auto-resume-at-loser
Determines whether I/O automatically resumes at the detached cluster for the
volumes in a consistency group when the cluster regains connectivity with its
peer cluster.
● Relevant only for multi-cluster consistency groups that contain distributed
volumes.
● Modifiable using the set command. Set this property to true to allow the
volumes to resume I/O without user intervention (using the resume-at-
loser command).
● true - I/O automatically resumes on the losing cluster after the inter-cluster
link has been restored.
● false (default) - I/O must be resumed manually after the inter-cluster link
has been restored.
● Leave this property set to false to give administrators time to restart the
application. Otherwise, dirty data in the host’s cache is not consistent with
the image on disk to which the winning cluster has been actively writing.
Setting this property to true can cause a spontaneous change of the view
of data presented to applications at the losing cluster. Most applications
cannot tolerate this data change. If the host flushes those dirty pages out
of sequence, the data image may be corrupted.
Display-only properties
active-clusters
For synchronous consistency groups, this property is always empty ([ ]).
Consistency Groups 75