Recovery for a failing alias unit control block (UCB)

For a parallel access volume, the status of a base UCB affects the status of its alias UCBs. The status of an alias UCB, however, might not affect the status of its base UCB. When the system detects a problem with an alias UCB, a recovery action applies to the base and its alias UCBs. If an alias UCB becomes boxed, you can unbox the alias with the following DEVSERV command:

     DEVSERV QPAVS,devn,UNBOX

Error messages that display in the following situations are the only indication that an alias UCB is boxed:

• The device is varied online
• A hardware change is activated
• The system is in recovery