If you use the SCAN function to determine the contents of a volume that is not defined to DFSMSrmm, you can use the details for the first file to add the volume and first file data set information to the DFSMSrmm CDS, using the following commands:

RMM AV volser DSN(dsname) ASDATE(crdate) JOBNAME(jobn)  
RMM CD dsname VOLUME(volser) JOBNAME(jobn) CRDATE(crdate) LABELNUMBER(dsseq) 
       STEP(step) RECFM(recfm) LRECL(lrecl) BLKSIZE(blksize) DEVNUM(device)