Suspending geographic mirroring

If you need to end TCP communications for any reason, such as placing your system in restricted state, you should suspend geographic mirroring first. This action temporarily stops mirroring between systems in a high-availability solution.

When you suspend mirroring, any changes that are made on the production copy of the independent disk pool are not being transmitted to the mirror copy.

Note: When you resume geographic mirroring, synchronization is required between the production and mirror copies. If geographic mirroring was suspended without tracking, then full synchronization occurs. This can be a lengthy process.

Suspending geographic mirroring when IBM® PowerHA® for i is installed

To use the PowerHA graphical interface to suspend geographic mirroring, follow these steps:

  1. In a Web browser, enter http://mysystem:2001, where mysystem is the host name of the system.
  2. Log on to the system with your user profile and password.
  3. Click PowerHA from the IBM Navigator for i window.
  4. On the PowerHA page, click Independent ASPs.
  5. On the Independent ASPs page, select Details... from the context menu of the independent disk pool for which you want to suspend geographic mirroring.
  6. On the Independent ASP Details page, select Suspend Mirroring from the Select Action menu below the mirroring status.
  7. Click Yes on the confirmation panel.

Suspending geographic mirroring with command line interface when IBM PowerHA SystemMirror® for i licensed program is installed

To suspend a geographic mirroring by using the command line interface, issue the following command:
  • CHGASPSSN SESSION(session-name) OPTION(*SUSPEND) where session-name is the name of your geographic mirroring session.

Suspending geographic mirroring when IBM PowerHA for i is not installed

To suspend geographic mirroring with IBM Navigator for i, follow these steps:

  1. In IBM Navigator for i, expand My Connections (or your active environment).
  2. Expand the system that owns the production copy of the geographically mirrored disk pool that you want to suspend.
  3. Expand Configuration and Service > Hardware > Disk Units > Disk Pools.
  4. Right-click the production copy of the Disk Pool you want to suspend and select Geographic Mirroring > Suspend Geographic Mirroring.

If you suspend with tracking, the system attempts to track changes that are made to those disk pools. This might shorten the length of the synchronization process by performing partial synchronization when you resume geographic mirroring. If tracking space is exhausted, then when you resume geographic mirroring, complete synchronization is required.

Note: If you suspend geographic mirroring without tracking changes, then when you resume geographic mirroring, a complete synchronization is required between the production and mirror copies. If you suspend geographic mirroring and you do track changes, then only a partial synchronization is required. Complete synchronization can be a lengthy process, anywhere from one to several hours, or longer. The length of time it takes to synchronize is dependent on the amount of data being synchronized, the speed of TCP/IP connections, and the number of communication lines that are used for geographic mirroring.