Administrator Guide

Resuming I/O at the losing cluster
During an inter-cluster link outage, an you might permit I/O to resume at one of the two clusters, the winning cluster.
About this task
I/O remains suspended on the losing cluster.
When the inter-cluster link restores, the winning and losing clusters re-connect, and the losing cluster discovers that the
winning cluster has resumed I/O without it.
Unless explicitly configured, I/O remains suspended on the losing cluster. This prevents applications at the losing cluster from
experiencing a spontaneous data change.
The delay allows you to shut down applications.
After stopping the applications, use the consistency-group resume-at-loser command to:
● Resynchronize the data image on the losing cluster with the data image on the winning cluster.
● Resume servicing I/O operations.
You can then safely restart the applications at the losing cluster.
To restart I/O on the losing cluster:
Steps
1. Use the ls command to display the operational status of the target consistency group.
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
2. Use the consistency-group resume-at-loser to restart I/O on the losing cluster.
VPlexcli:/clusters/cluster-1/consistency-groups/cg1> resume-at-loser -c cluster-2
This may change the view of data presented to applications at cluster cluster-2. You
should first stop applications at that cluster. Continue? (Yes/No) Yes
3. Use the ls command to verify the change in operational 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:: ok, details:: [] })]
passive-clusters []
recoverpoint-enabled false
storage-at-clusters [cluster-1, cluster-2]
virtual-volumes [dd1_vol, dd2_vol]
visibility [cluster-1, cluster-2]
Consistency Groups
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