Cannot "Vary Online" TSM Volume Groups

[tjspencer2]

For some reason we've encountered that our volume groups for CMOD are all offline.

We found this from TSM dsmadmc admin console: q vol   

And when we issue the command to vary online the volume group from the dsmadmc console we get the following error message:

10/26/16   13:00:56  ANR1314E Vary-on failed for disk volume
                      /archive01/7year/disk2 - reduced capacity (was 128000000
                      blocks, now 73728 blocks.

Of note, we can now no longer create a volume group > 2GB and can vary that online immediately but if a day elapses cannot vary that online either ??

[Justin Derrick]

I think there might be a nomenclature issue here. 

A volume group is an AIX Logical Volume Manager term for a collection of physical disks.

A volume (in TSM) is either a file, tape, or optical disk used to store data. 

A volume can be unavailable in TSM due to an issue with a filesystem.

It seems like you have a major OS-level issue if you can't create files over 2GB in size (are you using JFS instead of JFS2)?  The error message from TSM appears to indicate that the file has been truncated.  It might make sense to review your backups to see if the file was larger at a previous point in time, and consider restoring that.