We use the BACKUP SYSTEM utility to take daily backups of all our DB2 environments, initially to FlashCopy disks and then we perform a Dump to tape once the background copy has completed. So, the "commands" issued are
BACKUP SYSTEM FULL
BACKUP SYSTEM FULL DUMPONLY DUMPCLASS(DLM<retperiod>)
With later versions of z/OS (we're on 2.2) you have the ability to "break in" to both the background copy and the dump, so that you can perform a restore without having to wait for them to complete. However, HSM can and will interfere if you use the Common Dump Queue processing option.
The FRRECOV command has to run on the same LPAR / HSM member where the Dump is being processed. We found out that HSM will effectively override any SYSAFF parm coded in a batch job that issues the FRRECOV FORCE command and it will route the command to the HSM system that is least busy. The chances are that this won't be the one processing the Dump, so guess what - the FRRECOV fails! IBM have suggested that we raise an RFE for them to look at this; would this affect anybody else?