Resume write operations to the volumes that belong to the CU specified by the DEVN parameter. Relationships are not withdrawn.
The following example shows the command to resume write operations to the volumes that belong to the CU that contains device 4202.
FCWITHDR DEVN(X'4202') ACTION(THAW)
Since no relationship is withdrawn by performing this command, there is no change in the number of relationships after the command is executed.
Even if you do not issue this command, write operations to the volumes may be resumed implicitly if the SCP time elapses.