Using forced failover and failback during a planned Metro/Global Mirror outage

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Use this process to run failover operations from the local (A) site to the intermediate (B) site during a planned outage.

Before you begin

The following assumptions apply to your 3-site Metro/Global Mirror configuration:
  • You used incremental resynchronization to establish the relationship between your site A and site B volumes and between your site A and site C volumes.
  • You established a Global Mirror session at the local site. This means that Fibre Channel paths were established between all Global Mirror source and target pairs and between the master and subordinate storage systems.
The command examples use the following site identifiers:
  • Site A is identified as 2107-130165X
  • Site B is identified as 2107-75ALA2P
  • Site C is identified as 2107-183176O

About this task

This process uses forced failover and forced failback processing to establish a relationship between the C and A volumes without verification that this relationship already existed. A -force parameter has been added to the failoverpprc and failbackpprc commands to accommodate this processing.

Attention: Use the -force parameter only as directed. This parameter can cause severe damage to your data if it is misused. Contact your technical support representative before you attempt to use the -force parameter if your outage situation is outside the boundaries of this example.

Complete the following steps to failover and restore operations to the intermediate (B) site.

Procedure

  1. At the local site, ensure that data consistency is achieved between the site A and site B volumes. You can use freeze and unfreeze commands that are supported using external automation software to create data consistency to multiple Metro Mirror volume pairs.

    To freeze write activity to Metro Mirror primary volumes, complete the following steps:

    1. Freeze updates to the A volumes in Metro Mirror relationships across the affected LSSs. This ensures that the B volumes will be consistent at the time of the freeze process. (One command per LSS is required.)

      Enter the freezepprc command at the dscli command prompt with the following parameters and variables: 

      dscli> freezepprc -dev IBM.2107-130165X
-remotedev IBM.2107-75ALA2P 07-12
      The following represents an example of the output: 
      CMUC00161W freezepprc: Remote Mirror and Copy consistency group 07:12
 successfully created.
      As a result of the freeze action, the following processing occurs:
      • The established Remote Mirror and Copy paths between the LSS pairs are deleted.
      • The volume pairs that are associated with the source and target LSSs are suspended. During this time, the storage unit collects data that is sent to the A volumes in Metro Mirror relationships.
      • I/O to the Metro Mirror volume pairs is temporarily queued.
    2. Resume operations following a freeze. This operation—also called a thaw operation—allows I/O processing to resume for the specified volume pairs.

      Enter the unfreezepprc command at the dscli command prompt with the following parameters and variables:

      dscli> unfreezepprc -dev IBM.2107-130165X
-remotedev IBM.2107-75ALA2P 07:12
      The following represents an example of the output: 
      CMUC00198I unfreezepprc: Remote Mirror and Copy pair 07:12  
successfully thawed.
  2. Create a relationship from the C volumes to the A volumes, using the -force and -cascade parameters. No validation is done at site C to determine that site C is a secondary of site A.
    Note: For this step to succeed you must ensure that the Remote Mirror and Copy paths between all Global Mirror source and target pairs and between the Master and subordinate storage units have been created.
    Enter the failoverpprc command at the dscli prompt with the following parameters and variables:
    dscli> failoverpprc -dev storage_image_ID -remotedev storage_image_ID
-type gcp -cascade -force SourceVolumeID:TargetVolumeID

    Example

    dscli> failoverpprc -dev IBM.2107-183176O
-remotedev IBM.2107-130165X
-type gcp -cascade -force 1200-125f:1A00-1A5f

    The following represents an example of the output: 

    CMUC00196I failoverpprc: Remote Mirror and Copy pair 1200:1A00 
successfully reversed.
CMUC00196I failoverpprc: Remote Mirror and Copy pair 1201:1A01 
successfully reversed.
CMUC00196I failoverpprc: Remote Mirror and Copy pair 1202:1A02 
successfully reversed.
  3. End the Metro Mirror relationship between the A to B volumes at the B volumes intermediate site.
    Enter the rmpprc command at the dscli command prompt with the following parameters and variables: 
    dscli> rmpprc  -dev storage_image_ID  -remotedev storage_image_ID 
-at tgt -unconditional -quiet  TargetVolumeID
    Example
    dscli> rmpprc  -dev IBM.
2107-75ALA2P -remotedev IBM.
2107-130165X -at tgt -unconditional -quiet  1200-125f
  4. Redirect host I/O processing to the B volumes. Changes are recorded on the B volumes until the A volumes can be resynchronized with the B volumes. Also, Global Mirror continues to operate from site B to site C.
    Note: You can run in this configuration until the A site has recovered and you want to restore operations there. Begin the next step after the A volumes have been recovered and you're still in production on the B volumes.
  5. Copy changes from site C back to site A, using the -force parameter. Host I/O processing continues uninterrupted to the B volumes while the A volumes are made current. (The data is still flowing from B to C, so any changes made to B are being transferred to C and therefore will get from C to A.) This command copies the changes back to the A volumes that were made to the B volumes while hosts were running on the A volumes. (In a DS CLI environment, where the local and remote sites are not using the same management console, you have to use the management console of the remote site.)
    Enter the failbackpprc command at the dscli command prompt with the following parameters and variables:
    dscli> failbackpprc -dev storage_image_ID -remotedev storage_image_ID
-type gcp -force SourceVolumeID:TargetVolumeID
    Example
    dscli> failbackpprc -dev IBM.2107-183176O
-remotedev IBM.2107-130165X 
-type gcp -force 1200-125f:1A00-1A5f
    The following represents an example of the output: 
    CMUC00197I failbackpprc: Remote Mirror and Copy pair 1200:1A00 
successfully failed back.
CMUC00197I failbackpprc: Remote Mirror and Copy pair 1201:1A01 
successfully failed back.
CMUC00197I failbackpprc: Remote Mirror and Copy pair 1202:1A02 
successfully failed back.
  6. Wait for the first pass copy to complete from site C to site A. Issue the lspprc command if you want to monitor this activity and determine when the first pass status changes to “True.”
    Enter the lspprc command at the dscli command prompt with the following parameters and variables:
    dscli> lspprc -dev storage_image_ID -remotedev storage_image_ID
-l SourceVolumeID:TargetVolumeID
    Example
    dscli> lspprc -dev IBM.
2107-183176O -remotedev IBM.2107-75130165X
-l 1200-125f:1A00-1A5f
    The following represents the first two lines of the report generated by the lspprc command:
    ID State Reason Type
    Source-
    LSS
    Time-
    out
    (secs)
    Critical
    Mode
    First
    Pass
    Status
    IBM.2107-
    183176O
    /2101:
    IBM.2107-
    130165X
    /2101
    Copy
    Pend-
    ing
    		 -
    Global
    Copy
    IBM.2107-
    130165X
    /20
    		 300 Disabled True
    IBM.2107-
    183176O
    /2100:
    IBM.2107-
    130165X
    /2100
    Copy
    Pend-
    ing
    		 -
    Global
    Copy
    IBM.2107-
    130165X
    /20
    		 300 Disabled True
  7. Modify Global Copy relationships between the B and C volume pairs. Specify the NOCOPY option and initiate incremental resynchronization without initialization.
    Enter the mkpprc command at the dscli command prompt with the following parameters and variables: 
    dscli> mkpprc -dev storage_image_ID -remotedev storage_image_ID
-type gcp -incrementalresync enablenoinit -mode nocp 
SourceVolumeID:TargetVolumeID
    Example
    dscli> mkpprc -dev IBM.2107-75ALA2P
-remotedev IBM.2107-183176O -type gcp 
-incrementalresync enablenoinit -mode nocp 1200-125f:1A00-1A5f
    The following represents the first two lines of the output:
    CMUC00153I mkpprc: Remote Mirror and Copy volume pair 
relationship 1200:1A00 successfully created.
CMUC00153I mkpprc: Remote Mirror and Copy volume pair 
relationship 1201:1A01 successfully created.
  8. Begin the process to return production to site A. First, the Global Mirror session at site B must be stopped.
    Enter the rmgmir command at the dscli command prompt with the following parameters and variables: 
    dscli> rmgmir -dev storage_image_ID -lss LSS_ID -session session_ID
 Master_Control_Path_LSS_ID:Subordinate_Control_Path_LSS_ID
    Example
    dscli> rmgmir -dev IBM.2107-75ALA2P -quiet  -lss 07 -session 1
    The following represents an example of the output:
    CMUC00165I rmgmir: Global Mirror for session 1 successfully terminated.
  9. Verify that the Global Mirror session has ended.
    Enter the showgmir command at the dscli command prompt with the following parameters and variables:
    dscli> showgmir -dev storage_image_ID LSS_ID
    Example
    dscli> showgmir -dev IBM.2107-75ALA2P 10

    In the resulting report, the output indicates in the Copy State field whether the session has stopped.

  10. Suspend the B to C volume pairs. This step stops the transfer of data between the B and C volume pairs.
    Enter the pausepprc command at the dscli command prompt with the following parameters and variables:
    dscli> pausepprc -dev storage_image_ID_-remotedev storage_image_ID 
SourceVolumeID:TargetVolumeID
    Example
    dscli> pausepprc -dev IBM.
2107-75ALA2P -remotedev IBM.
2107-183176O 1200-125f:0700-075f
    The following represents an example of the output: 
    CMUC00157I pausepprc: Remote Mirror and Copy volume pair 1200:0700 relationship
successfully paused.
CMUC00157I pausepprc: Remote Mirror and Copy volume pair 1201:0701 relationship
successfully paused.

  11. Wait until all of the out-of-sync (OOS) tracks have drained from the C and A volume pairs and the OOS count at C is zero. If you want to monitor this process, issue the lspprc command to query the status of the C to A volume pairs in Global Copy relationships.
    Enter the lspprc command at the dscli command prompt with the following parameters and variables: 
    dscli> lspprc -dev storage_image_ID -remotedev storage_image_ID
 -l SourceVolumeID:TargetVolumeID
    Example
    dscli> lspprc -dev IBM.2107-183186O
-remotedev IBM.2107-75ALA2P  -l 
1200-125f:0700-075f
  12. Suspend the C and A volume pairs.
    Enter the pausepprc command at the dscli command prompt with the following parameters and variables:
    dscli> pausepprc -dev storage_image_ID_-remotedev storage_image_ID 
SourceVolumeID:TargetVolumeID
    Example
    dscli> pausepprc -dev IBM.2107-183176O
-remotedev IBM.2107-130165X 
1200-125f:0700-075f
    The following represents an example of the output: 
    CMUC00157I pausepprc: Remote Mirror and Copy volume pair 1200:0700 relationship
successfully paused.
CMUC00157I pausepprc: Remote Mirror and Copy volume pair 1201:0701 relationship
successfully paused.
  13. End the Global Copy relationship between the B to C volumes at the C remote volume site.
    Enter the rmpprc command at the dscli command prompt with the following parameters and variables: 
    dscli> rmpprc  -dev storage_image_ID  -remotedev storage_image_ID 
-at tgt -unconditional -quiet  TargetVolumeID
    Example
    dscli> rmpprc  -dev IBM.2107-75ALA2P
-remotedev IBM.2107-183176O 
-at tgt -unconditional -quiet  1A00-1A5f
  14. Reverse the direction by making the site A volumes a suspended primary site. Use the failoverpprc command for A to C with cascading allowed and specifying Global Copy mode.
    Enter the failoverpprc command at the dscli command prompt with the following parameters and variables:
    dscli> failoverpprc -dev storage_image_ID -remotedev storage_image_ID
 -type gcp -cascade SourceVolumeID:TargetVolumeID
    Example
    dscli> failoverpprc -dev IBM.
2107-130165X -remotedev IBM.2107-183176O
-type gcp -cascade 1A00-1A5f:1200-125f
    The following represents an example of the output: 
    CMUC00196I failoverpprc: Remote Mirror and Copy pair 1A00:1200 
successfully reversed.
CMUC00196I failoverpprc: Remote Mirror and Copy pair 1A01:1201 
successfully reversed.
  15. Resynchronize the A to C relationships.
    Enter the failbackpprc command at the dscli command prompt with the following parameters and variables:
    dscli> failbackpprc -dev storage_image_ID -remotedev storage_image_ID
 -type gcp  SourceVolumeID:TargetVolumeID
    Example
    dscli> failoverpprc -dev IBM.2107-130165X
-remotedev IBM.2107-183176O
-type gcp -cascade 1A00-1A5f:1200-125f
    The following represents an example of the output: 
    CMUC00196I failoverpprc: Remote Mirror and Copy pair 1A00:1200 
successfully failedback.
CMUC00196I failoverpprc: Remote Mirror and Copy pair 1A01:1201 
successfully failedback.
  16. Establish Metro Mirror relationships between the A to B volumes using the incremental resynchronization function and the override option. As a result of this step, the relationship verification is bypassed and the incremental resynchronization function stops. The system determines which data to copy, so a full volume copy is bypassed and only changes are copied from the A to B Metro Mirror volume pairs.
    Enter the mkpprc command at the dscli command prompt with the following parameters and variables:
    dscli> mkpprc -remotedev storage_image_ID -dev storage_image_ID
type mmir -mode nocp -incrementalresync override SourceVolumeID:TargetVolumeID
    Example 
    dscli> mkpprc -remotedev IBM.2107-75ALA2P
-dev IBM.2107-130165X -type mmir 
-mode nocp -incrementalresync override 2100-2107:2100-2107
    The following represents an example of the output:
    CMUC00153I mkpprc: Remote Mirror and Copy volume pair relationship 2100:2100 
successfully created.
CMUC00153I mkpprc: Remote Mirror and Copy volume pair relationship 2101:2101 
successfully created.
  17. Start incremental resynchronization with the initialization option on the B volumes in Metro Mirror relationships. Issue the mkpprc command at the intermediate site with the -incrementalresync enable parameter specified.
    Enter the mkpprc command at the dscli command prompt with the following parameters and variables: 
    dscli> mkpprc -dev storage_image_ID -remotedev storage_image_ID
-type mmir -mode nocp -incrementalresync enable SourceVolumeID:TargetVolumeID
    Example
    dscli> mkpprc -dev IBM.2107-130165X -remotedev 2107-75ALA2P -type mmir 
-mode nocp -incrementalresync enable 2100-2107:2100-2107
    The following represents an example of the output:
    CMUC00153I mkpprc: Remote Mirror and Copy volume pair relationship 2100:2100 
successfully created.
CMUC00153I mkpprc: Remote Mirror and Copy volume pair relationship 2101:2101 
successfully created.
  18. Wait for the B to A volume pairs to reach the full duplex state. Issue the lspprc command if you want to monitor this activity.
    Enter the lspprc command at the dscli command prompt with the following parameters and variables:
    dscli> lspprc -dev storage_image_ID -remotedev storage_image_ID
-l SourceVolumeID:TargetVolumeID
    Example
    dscli> lspprc -dev IBM.2107-75ALA2P
-remotedev IBM.2107-130165X  -l 
1200-125f:1A00-1A5f
  19. Start the Global Mirror session at the local site.
    Enter the mkgmir command at the dscli command prompt with the following parameters and variables (from the local site): 
    dscli> mkgmir -dev storage_image_ID -lss LSS_ID -session session_ID
    Example
    dscli> mkgmir -remotedev IBM.2107-75ALA2P  -lss 07 -session 31
    The following represents an example of the output:
    CMUC00162I mkgmir: Global Mirror for session 31 successfully started.

    When this step is processed, the Metro/Global Mirror operations are running from site B to site A to site C. You are now ready to transition back to your original configuration, where site A is your production site.

  20. Quiesce host I/O processing to the B volumes.
  21. Suspend the B to A processing.
    Enter the pausepprc command at the dscli command prompt with the following parameters and variables:
    dscli> pausepprc -dev storage_image_ID_-remotedev storage_image_ID 
SourceVolumeID:TargetVolumeID
    Example
    dscli> pausepprc -dev IBM.2107-75ALA2P
-remotedev IBM.2107-130165X 
1200-125f:0700-075f
    The following represents an example of the output: 
    CMUC00157I pausepprc: Remote Mirror and Copy volume pair 1200:0700 relationship
successfully paused.
CMUC00157I pausepprc: Remote Mirror and Copy volume pair 1201:0701 relationship
successfully paused.
  22. Create a relationship from the C volumes to the A volumes using the failoverpprc command with the -force and -cascade parameters specified.
    Enter the failoverpprc command at the dscli prompt with the following parameters and variables:
    dscli> failoverpprc -dev storage_image_ID -remotedev storage_image_ID
-type gcp -cascade -force SourceVolumeID:TargetVolumeID

    Example

    dscli> failoverpprc -dev IBM.2107-183176O
-remotedev IBM.2107-75ALA2P -type
gcp -cascade  -force 1200-125f:1A00-1A5f

    The following represents an example of the output: 

    CMUC00196I failoverpprc: Remote Mirror and Copy pair 1200:1A00 
successfully reversed.
CMUC00196I failoverpprc: Remote Mirror and Copy pair 1201:1A01 
successfully reversed.
CMUC00196I failoverpprc: Remote Mirror and Copy pair 1202:1A02 
successfully reversed.
  23. End the Global Copy relationships between the B and A volume pairs at the local site.
    Enter the rmpprc command at the dscli command prompt with the following parameters and variables:
    dscli> rmpprc  -dev storage_image_ID  -remotedev storage_image_ID 
-at tgt -unconditional -quiet  TargetVolumeID
    Example
    dscli> rmpprc  -dev IBM.2107-130165X
-remotedev IBM.2107-75ALA2P 
-at tgt -unconditional -quiet  1A00-1A5f
    The following represents an example of the output:
    CMUC00155I rmpprc: Remote Mirror and Copy volume pair 1200:0700 relationship 
successfully withdrawn.
CMUC00155I rmpprc: Remote Mirror and Copy volume pair 1201:0701 relationship 
successfully withdrawn.
  24. Resume host I/O processing to the A volumes.
  25. Copy changes from site C back to site A, using the -force parameter.
    Enter the failbackpprc command at the dscli command prompt with the following parameters and variables:
    dscli> failbackpprc -dev storage_image_ID -remotedev storage_image_ID
 -type gcp  -force SourceVolumeID:TargetVolumeID
    Example
    dscli> failoverpprc -dev IBM.2107-183176O
-remotedev IBM.2107-130165X
-type gcp -force 1A00-1A5f:1200-125f
    The following represents an example of the output: 
    CMUC00196I failoverpprc: Remote Mirror and Copy pair 1A00:1200 
successfully failedback.
CMUC00196I failoverpprc: Remote Mirror and Copy pair 1A01:1201 
successfully failedback.
    Note: Global Mirror processing continues to operate with site A volumes to site C volumes.
  26. Wait for the first pass copy to complete from site C to site B. Issue the lspprc command if you want to monitor this activity and determine when the first pass status changes to “True.”
    Enter the lspprc command at the dscli command prompt with the following parameters and variables:
    dscli> lspprc -dev storage_image_ID -remotedev storage_image_ID
-l SourceVolumeID:TargetVolumeID
    Example
    dscli> lspprc -dev IBM.2107-183176O
-remotedev IBM.2107-75ALA2P  -l 
1200-125f:1A00-1A5f
  27. Modify Global Copy relationships between the A and C volume pairs. Specify the NOCOPY option and initiate incremental resynchronization without initialization.
    Enter the mkpprc command at the dscli command prompt with the following parameters and variables: 
    dscli> mkpprc -dev storage_image_ID -remotedev storage_image_ID
-type gcp -incrementalresync enablenoinit -mode nocp 
SourceVolumeID:TargetVolumeID
    Example
    dscli> mkpprc -dev IBM.2107-130165X
-remotedev IBM.2107-183176O -type gcp 
-incrementalresync enablenoinit -mode nocp 1200-125f:1A00-1A5f
    The following represents the first two lines of the output:
    CMUC00153I mkpprc: Remote Mirror and Copy volume pair 
relationship 1200:1A00 successfully created.
CMUC00153I mkpprc: Remote Mirror and Copy volume pair 
relationship 1201:1A01 successfully created.
  28. Begin the process to include your B site in the 3-site Metro/Global Mirror configuration with production on site A. The Global Mirror session between the A, C, and D volumes must be stopped.
    Enter the rmgmir command at the dscli command prompt with the following parameters and variables: 
    dscli> rmgmir -dev storage_image_ID -lss LSS_ID -session session_ID
 Master_Control_Path_LSS_ID:Subordinate_Control_Path_LSS_ID
    Example
    dscli> rmgmir -dev IBM.2107-130165X -quiet  -lss 07 -session 2
    The following represents an example of the output:
    CMUC00165I pausegmir: Global Mirror for session 2 successfully paused.
  29. Suspend the A to C volume pairs.
    Enter the pausepprc command at the dscli command prompt with the following parameters and variables:
    dscli> pausepprc -dev storage_image_ID_-remotedev storage_image_ID 
SourceVolumeID:TargetVolumeID
    Example
    dscli> pausepprc -dev IBM.2107-130165X
-remotedev IBM.2107-183176O 
1200-125f:0700-075f
    The following represents an example of the output: 
    CMUC00157I pausepprc: Remote Mirror and Copy volume pair 1200:0700 relationship
successfully paused.
CMUC00157I pausepprc: Remote Mirror and Copy volume pair 1201:0701 relationship
successfully paused.
  30. End the Global Copy relationships between the A to C volumes at the remote site.
    Enter the rmpprc command at the dscli command prompt with the following parameters and variables:
    dscli> rmpprc  -dev storage_image_ID  -remotedev storage_image_ID 
-at tgt -unconditional -quiet  TargetVolumeID
    Example
    dscli> rmpprc  -dev IBM.
2107-183176O  -remotedev IBM.
2107-130165X 
 -at tgt -unconditional -quiet  1A00-1A5f
    The following represents an example of the output:
    CMUC00155I rmpprc: Remote Mirror and Copy volume pair 1200:0700 relationship 
successfully withdrawn.
CMUC00155I rmpprc: Remote Mirror and Copy volume pair 1201:0701 relationship 
successfully withdrawn.
  31. Wait until all of the out-of-sync (OOS) tracks have drained from the C to B volume pairs and the OOS count is zero. If you want to monitor this process, issue the lspprc command to query the status of the C to B volume pairs in Global Copy relationships.
    Enter the lspprc command at the dscli command prompt with the following parameters and variables: 
    dscli> lspprc -dev storage_image_ID -remotedev storage_image_ID
 -l SourceVolumeID:TargetVolumeID
    Example 
    dscli> lspprc -dev IBM.2107-75ALA2P
-remotedev IBM.2107-183186O  -l 
1200-125f:0700-075f
  32. Suspend the C to B volume pairs.
    Enter the pausepprc command at the dscli command prompt with the following parameters and variables:
    dscli> pausepprc -dev storage_image_ID_-remotedev storage_image_ID 
SourceVolumeID:TargetVolumeID
    Example
    dscli> pausepprc -dev IBM.2107-183176O
-remotedev IBM.2107-75ALA2P 
1200-125f:0700-075f
    The following represents an example of the output: 
    CMUC00157I pausepprc: Remote Mirror and Copy volume pair 1200:0700 relationship
successfully paused.
CMUC00157I pausepprc: Remote Mirror and Copy volume pair 1201:0701 relationship
successfully paused.
  33. Reverse the direction by making the site B volumes a suspended primary site. Use the failoverpprc command for B to C specifying the Global Copy mode and that cascading is allowed.
    Enter the failoverpprc command at the dscli command prompt with the following parameters and variables:
    dscli> failoverpprc -dev storage_image_ID -remotedev storage_image_ID
 -type gcp -cascade SourceVolumeID:TargetVolumeID
    Example
    dscli> failoverpprc -dev IBM.2107-75ALA2P
-remotedev IBM.2107-183176O
-type gcp -cascade 1A00-1A5f:1200-125f
    The following represents an example of the output: 
    CMUC00196I failoverpprc: Remote Mirror and Copy pair 1A00:1200 
successfully reversed.
CMUC00196I failoverpprc: Remote Mirror and Copy pair 1A01:1201 
successfully reversed.
  34. Resynchronize the C to B relationships.
    Enter the failbackpprc command at the dscli command prompt with the following parameters and variables:
    dscli> failbackpprc -remotedev storage_image_ID -dev storage_image_ID
 -type gcp  SourceVolumeID:TargetVolumeID
    Example
    dscli> failoverpprc -remotedev IBM.
2107-183176O -dev IBM.2107-75ALA2P
-type gcp -cascade 1A00-1A5f:1200-125f
    The following represents an example of the output: 
    CMUC00196I failoverpprc: Remote Mirror and Copy pair 1A00:1200 
successfully failedback.
CMUC00196I failoverpprc: Remote Mirror and Copy pair 1A01:1201 
successfully failedback.
  35. Establish Metro Mirror relationships between the A to B volumes using the incremental resynchronization function and the override option. As a result of this step, the relationship verification is bypassed and the incremental resynchronization function stopped. The system determines which data to copy, so a full volume copy is bypassed and only changes are copied from the A to B Metro Mirror volume pairs.
    Enter the mkpprc command at the dscli command prompt with the following parameters and variables:
    dscli> mkpprc -dev storage_image_ID -remotedev storage_image_ID
type mmir -mode nocp -incrementalresync override SourceVolumeID:TargetVolumeID
    Example 
    dscli> mkpprc -dev IBM.2107-130165X
-remotedev IBM.2107-75ALA2P -type mmir 
-mode nocp -incrementalresync override 2100-2107:2100-2107
    The following represents an example of the output:
    CMUC00153I mkpprc: Remote Mirror and Copy volume pair relationship 2100:2100 
successfully created.
CMUC00153I mkpprc: Remote Mirror and Copy volume pair relationship 2101:2101 
successfully created.
  36. Start incremental resynchronization with the initialization option on the A volumes in the Metro Mirror relationships. Use the mkpprc command at the local site with the -incrementalresync enable parameter specified.
    Enter the mkpprc command at the dscli command prompt with the following parameters and variables:
    dscli> mkpprc -dev storage_image_ID -remotedev storage_image_ID
-type mmir -mode nocp -incrementalresync enable SourceVolumeID:TargetVolumeID
    Example
    dscli> mkpprc -dev IBM.2107-130165X
-remotedev IBM.2107-75ALA2P -type mmir 
-mode nocp -incrementalresync enable 2100-2107:2100-2107
    The following represents an example of the output:
    CMUC00153I mkpprc: Remote Mirror and Copy volume pair relationship 2100:2100 
successfully created.
CMUC00153I mkpprc: Remote Mirror and Copy volume pair relationship 2101:2101 
successfully created.
  37. Wait for A to B to reach the full duplex state and for the first pass of the Global Copy processing of the B and C volumes to complete.
    You can monitor this activity by entering the lspprc command to query the status of the B to C volume pairs in Global Copy relationships.
    Enter the lspprc command at the dscli command prompt with the following parameters and variables: 
    dscli> lspprc -dev IBM.2107-75ALA2P
-remotedev IBM.2107-75ALA2P  -l 
-fmt default 1200-125f:0700-075f
  38. Start Global Mirror at the intermediate site. Now that the original infrastructure has been restored, you can resume the Global Mirror session.
    Enter the mkgmir command at the dscli command prompt with the following parameters and variables:
    dscli> mkgmir -dev IBM.2107-75ALA2P -session 1 -lss 07
    The following represents an example of the output: 
    CMUC00164I resumegmir: Global Mirror for session 1 successfully resumed.
  39. Verify that consistency groups are forming successfully.
    Enter the showgmir -metrics command at the dscli command prompt with the following parameters and variables: 
    dscli> showgmir -metrics 07

    The following represents an example of the output:

    ID
    Total
    Failed
    CG
    Count
    Total
    Succes-
    sful CG
    Count
    Succes-
    sful CG
    Percen-
    tage
    Failed
    CG after
    Last
    Success
    Last
    Succes-
    sful CG
    Form
    Time
    Coord.
    Time
    (milli-
    seconds)
    CG
    Interval
    Time
    (sec-
    onds)
    IBM.2107
    -130165X
    /07
    		 0 55 100 0
    10/20/
    2005
    11:38:25
    MST
    		 50 0
    Max
    CG
    Drain
    Time
    (seconds)
    First
    Failure
    Control
    Unit
    First
    Failure
    LSS
    First
    Failure
    Status
    First
    Failure
    Reason
    First
    Failure
    Master
    State
    Last
    Failure
    Control
    Unit
    Last
    Failure
    LSS
    30 - -
    No Error
    		 - - - -
    Last
    Failure
    Status
    Last
    Failure
    Reason
    Last
    Failure
    Master
    State
    Previous
    Failure
    Control
    Unit
    Previous
    Failure
    LSS
    Previous
    Failure
    Status
    Previous
    Failure
    Reason
    Previous
    Failure
    Master
    State
    No Error
    		 - - - -
    No Error
    		 - -