How long does JSF retain archived output?

Q:

How many days will JSF retain archived output?
The only parameter I see related to this is KEEPDAYS, max = 99.
Does this mean we can keep output for 99 days? Or 99 days on the database?
Is there another parameter that indicates how many days output is kept on backup tape? 

A:

KEEPDAYS indicates the number of days on the ISPF database. There is not another parameter as such that indicates how many days output is kept on backup tapes. That is determined by how long your JSF backup tapes are cataloged and available on your z/OS and tape management systems. As long as a backup tape is still cataloged and exists, it can be used by JSF to restore job(s) it contains back onto JSF ISPF, via the JSF ISPF Restore function.