Recovering from a link failure between near sites in a cascade topology

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To recover from a link failure between near sites in a cascade topology, you verify the state of the consistent group and choose a recovery task.

Verify that the 050993 3-site consistency group is now in STOPPED State notification is received. To view the event notification, see Informational events.

Enter the ls3sitercconsistgrp command to verify the state of the consistency groups.

In the resulting output, the state of the consistency groups is stopped.

[root@ORCH-HOST cli]# ls3sitercconsistgrp
name state            primary periodic_copy_source sync_copy_state         periodic_copy_state freeze_time cycle_period   status
CG0  stopped          AuXNear Master              consistent_disconnected idling                        0 350            sync_link_offline

To complete the link failure recovery, complete one of the following tasks.
- Option 1 is to enter the ch3sitercconsistgrp -periodicsrc command to take immediate action and move the consistency group to the 2site_periodic state.
```
[root@ORCH-HOST cli]# ch3sitercconsistgrp -periodicsrc AuxNear CG0 
```
  Enter the ls3sitercconsistgrp command to verify the state of the consistency groups.
```
[root@ORCH-HOST cli]# ls3sitercconsistgrp
name state            primary periodic_copy_source sync_copy_state         periodic_copy_state freeze_time cycle_period status
CG0  2site_periodic   AuXNear AuxNear              consistent_disconnected      stopped                         350     sync_link_offline
```
- Option 2 is to recover from the periodic state or the stopped state without moving into the 2site_periodic state. Then, restore the link. Restoring the link might change the 3-site consistency group state to 3site_consistent.
  If the sync_copy_state is consistent_stopped, and the state of the 3-site consistency group does not change to 3site_consistent, complete the following steps.
  1. Enter the ls3sitercconsistgrp command to verify the state of the consistency groups.
```
[root@ORCH-HOST cli]# ls3sitercconsistgrp 
name state            primary periodic_copy_source sync_copy_state         periodic_copy_state freeze_time cycle_period   status
CG0  2site_periodic   AuXNear Master              consistent_stopped      idling                           350            online
```
  2. Enter the ch3sitercconsistgrp -join command to recover from the stopped state without entering the 2site_periodic state.
```
[root@ORCH-HOST cli]# ch3sitercconsistgrp -join Master CG0  
```
  3. Enter the ls3sitercconsistgrp command to verify the state of the consistency groups.
```
[root@ORCH-HOST cli]# ls3sitercconsistgrp
name state            primary periodic_copy_source sync_copy_state         periodic_copy_state freeze_time cycle_period status
CG0  3site_consistent AuXNear Master              consistent_synchronized stopped                       0 350          online
```
    The state change might take time and is only reflected after the sync_copy_state changes to consistent_synchronized.