Administrator Guide

When the inter-cluster link is restored, the clusters learn that I/O has proceeded independently. I/O continues at both clusters
until you pick a winning cluster whose data image will be used as the source to synchronize the data images.
In the following example, I/O resumed at both clusters during an inter-cluster link outage. When the inter-cluster link is restored,
the two clusters come back into contact and learn that they have each detached the other and carried on I/O.
Steps
1. Use the ls command to display the consistency group’s operational status at both clusters.
VPlexcli:/clusters/cluster-1/consistency-groups/cg1> ls
Attributes:
Name Value
-------------------- -----------------------------------------
active-clusters [cluster-1, cluster-2]
cache-mode synchronous
detach-rule no-automatic-winner
operational-status [(cluster-1,{ summary:: ok, details:: [requires-resolve-
conflicting-detach] }),
(cluster-2,{ summary:: ok, details:: [requires-resolve-conflicting-detach] })]
passive-clusters []
recoverpoint-enabled false
storage-at-clusters [cluster-1, cluster-2]
virtual-volumes [dd1_vol, dd2_vol]
visibility [cluster-1, cluster-2]
Contexts:
advanced recoverpoint
2. Use the resolve-conflicting-detach command to select cluster-1 as the winner.
VPlexcli:/clusters/cluster-1/consistency-groups/cg1> resolve-conflicting-detach -c
cluster-1
This will cause I/O to suspend at clusters in conflict with cluster cluster-1,
allowing you to stop applications at those clusters. Continue? (Yes/No) Yes
Cluster-2’s modifications to data on volumes in the consistency group since the link outage started are discarded.
Cluster-2's data image is then synchronized with the image at cluster-1.
I/O gets suspended at cluster-2 if the auto-resume policy is false.
3. Use the ls command to verify the change in operation status:
VPlexcli:/clusters/cluster-1/consistency-groups/cg1> ls
Attributes:
Name Value
------------------- ----------------------------------------------------------
active-clusters [cluster-1, cluster-2]
cache-mode synchronous
detach-rule no-automatic-winner
operational-status [(cluster-1,{ summary:: ok, details:: [] }),
(cluster-2,{ summary:: suspended, details:: [requires-resume-at-
loser] })]
passive-clusters []
recoverpoint-enabled false
storage-at-clusters [cluster-1, cluster-2]
virtual-volumes [dd1_vol, dd2_vol]
visibility [cluster-1, cluster-2]
Contexts:
advanced recoverpoint
● At cluster-1, I/O continues, and the status is ok.
● At cluster-2, the view of data has changed and hence I/O is suspended.
4. Use the consistency-group resume-at-loser command to resume I/O to the consistency group on cluster-2.
Consistency Groups
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