Of the sites we support, 86 of them use HSM and 44 use FDR/ABR/CPK. The rest use plain old DF/dss that we run as full volume backups weekly with incremental backups daily (twice a day for some of them). Some of the volumes that don't change often or make little sense to backup daily or weekly (Spool volumes, etc.) we backup monthly just so that we have something to restore if D.R> is necessary.
We make sure to email the listings to several places, and the tapes are kept with retention periods that varies for the various sites, some are 30 days, some are 60 or more, it depends on how elaborate your recovery scenario is. The entire purpose of backups is to recover data, so you need to figure out how you want to do that and how current that data needs to be to get your goals satisfied and works backwards to the backups from that point. If you have some volumes that loosing more than a couple hours of data would be a disaster, then you need to run your backups for that data a lot more frequent than something that you can recover easily from other sources. Another item you have to be aware of is that if you use virtual tape, you have to have a way to recover them if you lose the device and don't' have any "real" tapes to use to recover them. You would be surprised to hear how many sites don't think of what they will do if the device goes belly up. Some of our sites offload to large tape on a frequency of their choice, but some of them simply copy the virtual files on the back end directly to external (i.e. USB hard drives) disks and store them offsite on a rotation basis. It seems pretty hokey, but it actually works for some of them and I have actually participated in several actual DR's where we used them to recover the tapes to the DR site's Virtual system. It's not my preferred method, but it's much better than the alternative. It's actually pretty straightforward once you decide how you will recover things, trying to move the other direction (deciding on backups then figuring out how to recover) is a really bad approach. Brian ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
