Hi
This is really a DB2z question rather than a ZD&T question, but let me try.
A storage groups maps to one or more disk volumes through the SMS definitions.
So I would add a new SMS-managed disk volume, find the SMS ACS routine that maps to your storage group, and then add the disk to that.
If you don't know how, you should get SMS- and DB2-skilled people to help you. Or read the manuals carefully.
Br
Michael Erichsen,
Xact Consulting
MichaelErichsen,Xact