Recovering an HDR cluster after the secondary server became the primary server

If a secondary server in an HDR cluster became the primary server after the original primary server failed, you can use a script to reestablish the original primary and convert the current primary server back to a secondary server.

Suppose the primary server, named srv_pri, has encountered an error that has caused it to fail over to an HDR secondary server named srv_hdr_sec. At this point, the primary server is srv_hdr_sec, and any other secondary servers in the cluster are now pointing to srv_hdr_sec.

To restore the cluster to the way it was before srv_pri failed over, follow these steps:

  1. Initialize srv_pri as the HDR secondary server by running the appropriate command:
    UNIX systems:
    $INFORMIXDIR/bin/ srv_hdr_sec
    Windows systems:
    hdrmksec.bat srv_hdr_sec
  2. Change srv_pri to the primary server by running:
    onmode -d make primary srv_pri
    This command makes srv_pri the primary server, and redirects any other secondary servers in the cluster to point to the new primary server. The command also shuts down the old HDR primary (srv_hdr_sec) because only a single primary server can exist in a high-availability environment.
  3. Initialize srv_hdr_sec as the HDR secondary server by running the following command:
    On UNIX systems:
    $INFORMIXDIR/bin/ srv_pri
    On Windows systems:
    hdrmksec.bat srv_pri

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