I also have been working with MVS since before (just) 1980, and I can honestly tell you that the correct answer is "It depends". The important part is to actually do the maintenance and not get (too) far behind. There are a lot of sites that tend to get several releases (years) behind and then they end up calling me (or someone else) to get them back up to "date". The important thing is that you do some sort of maintenance on some sort of schedule. The IBM REDBOOK pointed to previously in this thread is actually very good about giving hints on how you should perform the maintenance aspect of our Systems Programming jobs.
Maintenance used to take a REALLY long time, and now it's actually fairly simple. There are a lot of factors to consider and the more complex your site, the higher the difficulty level in keeping "relatively" current. You really have to plan your system for the method you choose. There are those that feel that they can apply maint on a fixed schedule, and if that works for them then that is fine. There are others that believe that you should install a new release once a year (or two) and only put on maintenance that you absolutely need in order to fix a problem that you are experiencing. That's fine as well. What ever you decide, it will be great for you and your site. Personally, I like the method of installing a new release periodically and applying the current maintenance (as needed), and then doing all (or most) of the hyper fixes in between. It's a little more work, but it tends to work out good for me. I don't have a fixed schedule, but I try to keep the sites that I maintain at "about" the same level. There are quite a few. My reasons are because if I run into a problem at one site, I can be proactive and fix it for the others as well. It's terrible to admit, but this way I look really good because the ones that reported the problem are happy that I "fixed" it for them, and the others are totally thrilled that I was "looking out" for them. It's sort of a win-win thing, but I have to admit that it is a little more work on my end to keep everyone relatively equal. Also, by equal, I don't necessarily meant hat they are even at the same release, I maintain sites from 1.4 (unfortunately, and until recently I still had several OS/390 sites) ) to 1.12, but (where I can) they are all at the same level of maintenance. Most fixes are applied back to the older releases (as long as they are supported) so it's not as hard or as complex as it might seem. I try to keep them all as current as possible, but not all of them want (or need) to be on z/OS 1.12 so I try to be as flexible as possible, while keeping them all current (as much as possible) with maintenance. I urge you to find a way that works for you and try to be flexible. If you find that you need to change to meet the needs of your site, don't say "no" just because it doesn't meet your "schedule" of maintenance. Try to be a service to your site and try to be as accessible as possible. The "old days" of the wall between systems and the rest of the site are long gone (or should be). I miss them sometimes, but not very much. :) ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html