6.13.1. Reset a Single Site in a Multi-Site/Active-Active Topology

Warning

The procedures in this section are designed for the Multi-Site/Active-Active topology ONLY. Do NOT use these procedures with Composite Active/Active, Composite Active/Passive or Composite Dynamic Active/Active clusters.

Under certain conditions, dataservices in a Multi-Site/Active-Active configuration may drift and/or become inconsistent with the data in another dataservice. If this occurs, you may need to re-provision the data on one or more of the dataservices after first determining the definitive source of the information.

In the following example the west service has been determined to be the definitive copy of the data. To fix the issue, all the datasources in the east service will be reprovisioned from one of the datasources in the west service.

The following is a guide to the steps that should be followed. In the example procedure it is the east service that has failed:

  1. Put the dataservice into MAINTENANCE mode. This ensures that Tungsten Cluster will not attempt to automatically recover the service.

    cctrl [east]> set policy maintenance
  2. Stop all services running on the primary node in east:

    shell east> stopall
    shell east> mm_replicator stop
  3. Stop replicator services running on the replica nodes in east:

    shell east> mm_replicator stop
  4. Disable cross-site replication in west:

    shell west> mm_trepctl offline
  5. Reprovision the Primary node in east using one of the replica nodes in west as the source

  6. Restart the services on the Primary node in east:

    shell east> startall
  7. Reprovision the replica nodes in east using one of the primary node in east as the source

  8. Offline and reset the replicators on all nodes in east

    shell east> trepctl offline
    shell east> trepctl reset -all -y
    shell east> trepctl online
  9. Ensure all nodes in the east cluster are online by checking in cctrl

    shell east> echo ls | cctrl
    shell east> trepctl status
  10. Reset the cross-site replicators in west, and bring back online:

    shell east> mm_trepctl reset -all -y
    shell east> mm_trepctl online
  11. Bring the cross-site replicators in east, online:

    shell east> mm_replicator start
  12. Set the cluster to normal operational state:

    cctrl> router * online
    cctrl> set policy automatic