I would make a backup tape that I intended to keep forever and I would save DLO *all to this tape and then delete what you determine you no longer need on the system. You still need to backup anything that is on the system and your backup should have the following 2 commands in addition to backing up libraries.
SAVDLO DLO(*ALL) DEV(TAP01) ENDOPT(*LEAVE)
SAV DEV(‘/QSYS.LIB/TAP01.DEVD’) OBJ((‘/QSYS.LIB’ +
*OMIT) (‘/QDLS’ *OMIT) (‘/*’)) +
The save DLO *all saves whatever is in the DLO.
The other SAV command saves whatever is present out on the IFS that is not DLO.
Please note these 2 commands are for using TAP01 and should be changed to whatever your tape drive is.
The main point is to backup whatever is present on the system. If your disk drives crash or you experience some other serious failure you want to get back what is there. Unless you have a lot of stuff these 2 commands shouldn’t add more than 10 to 15 minutes to your backup. That is unless you have a slow system and a slow tape drive.
It is very important to have these 2 commands in your backup. A lot of shops miss these commands thinking that all they need is contained in libraries. Take a look at the Backup & recovery publications they have much more detail on these commands and their implications. These 2 commands are part of what gets executed when you take option 21 to save the entire system.