If a TCP/IP stack fails, and that stack is a target stack for a DRVIPA using the Sysplexports function, the distributor stack for that DRVIPA returns all ephemeral ports allocated to the failing stack back to the available pool in the EZBEPORT structure. If the distributor stack for a DRVIPA fails, and has no backup stack designated, the target stacks for that DRVIPA return all ephemeral ports assigned to each target stack back to the available pool. The ephemeral ports assigned to a failing distributor stack (with no backup) are recovered when the distributor stack is restarted and requests an ephemeral port for the first time.