Failure of the local storage system

If the local storage system fails, processing can be resumed in a short time using the target units of the remote storage system. Data may be inconsistent if the remote link or the target unit had already failed before the local failure occurred.
If paging is affected, usually the local system also fails (see section "Failure of the local storage system and of the local system").

Actions in the local system

1. Use /ATTACH-DEVICE to attach the source and target units (see the “Commands” manual [1]).

2. Set the target units to READY. If the remote storage system contains only target units which are affected by the failure, the entire local storage system can be specified. Switchover takes place simultaneously for all the devices affected.

   /HOLD-REMOTE-COPY UNIT=*BY-STORAGE(SERIAL-NUMBER=<local serialnumber>
     ,LOGICAL-VOLUMES=*ALL-SOURCE-UNITS)
   

   For this function, the values DETACHED-DEVICES=*ACCEPT and NOT-DEFINED-DEVICES=*ACCEPT must be set for SYSTEM-ADMIN-SCOPE or TASK-ADMIN-SCOPE.

   If not all target units of the remote storage system are affected by the failure, all defined BS2000 volumes, all attached BS2000 volumes or the units can optionally be specified separately by means of their MN.

   The *BY-VOLUME operand can only be used if the source unit was accessible, i.e. the VSN could be read there. The *BY-PUBSET operand cannot be used for the switchover because of the failure.

3. Check data integrity (see section "Data integrity after a failure").

4. Import the pubsets on the target units and start the applications.