Only now i got it: "IOS", not "I OS". Actually this is not a mainframe but a midrange system, just like the p-series - in fact it is the same hardware.

This system was formerly called "AS/400" and the OS "OS/400" and you will find probably a lot more under these terms than under "IOS". Most of it, even the most outdated information, will probably still apply because the system hasn't changed that much for the last 20 years.

The AS/400 is quite radically different from anyother machine (for instance it has a linear address space which spans memory AND disk space - you move a file and it is dumped from memory to disk) and getting around the concepts is probably quite hard first.

On the other hand the AS/400 is famous for needing next to no administration at all. There are many companies owning a AS/400 and having had no Sysadmin for the last 15 years. Try that with a Unix system, it would be long broken.

The network is an alien thing too: it is called 5250 and works similar to (but is still different from) the SNA system and the 3270 data stream the IBM mainframes use.

Now for the good news: because IOS systems work in p-Series hardware there are still VIOS and HMC and they work absolutely the same way as you are accustomed to. Just the LPARs running IOS are different (inside - they are still the same LPARs from outside, say, from the viewpoint of the VIOS or the HMC).

I hope this helps.

bakunin