When the IBM FE is working on a tape drive, it is usually advisable to put the CHPID
offline, to prevent the CHPID from communicating with the mainframe while IBM is fixing and testing.|
This is done via the console commands as follows:
Example - IBM wants to repair drive 300:
Put both tape drives Offline
Verifiy both actually went Offline.
This puts offline the path to those devices thru that CHPID
Only have 2 devices but 16 are defined and must be in PATH command
This puts the CHPID Offline. IBM can do it's thing.
When IBM is done:
This puts the CHPID back online
This should also put the PATH back Online
This puts the devices back Online
For the other tape drives, adjust the addresses and CHPIDs as appropriate:
Drives 310-311 are on CHPID 1A
Drives 320-321 are on CHPID 11
If an address will not go Offlne, enter S XXX then do the D U,,,aaa,2 again to see if it went offline
If not, do D U,,ALLOC,aaa,2 to see what job is allocated to device 'aaa' and cancel that job.