You are still limited to a maximum linear VSAM file size of about 4GB. You cannot define a single large dataset to used up the entire mod-27 like you can on an AIX system.
-----Original Message----- From: Sam Sheppard [mailto:[EMAIL PROTECTED] Sent: Thursday, July 10, 2003 2:32 PM To: [EMAIL PROTECTED] Subject: TSM and mod-27 devices ---------------------------- Top of message ---------------------------- >>--> 07-10-03 14:25 S.SHEPPARD (SHS) TSM and mod-27 devices Well, I'll take a stab at this. We just converted from an old RVA to an ESS-800 and wondered the same thing. General agreement seemed to be there weren't really any advantages to mod-27 unless you're running out of addresses and there were some downsides, mainly the inability to start more than one I/O to the device at a time without PAV. I'm not really sure what kind of problems you might see, performancewise. Might be OK. There is also the size limitations on the log/db which would prevent you from using the entire 25GB with one dataset. There are probably other considerations, but we had no reason not to just stick to lots of mod-3s. I know I asked the same thing here about a month ago and didn't get much feedback. Anyone else tried this? Sam Sheppard San Diego Data Processing Corp. (858)-581-9668 -----------------------------------------------------------------------` ---------------------------- Top of message ---------------------------- >>--> 07-10-03 07:46 ..NETMAIL () TSM and mod-27 devices Date: Thu, 10 Jul 2003 09:39:35 -0500 From: "Glass, Peter" <[EMAIL PROTECTED]> Subject: TSM and mod-27 devices To: [EMAIL PROTECTED] _________________________________Top_of_Message_____________________________ ____ We're running a V5 TSM Server on an MVS platform, and considering the use of mod-27s for its DASD needs. Are there any known issues regarding the use of mod-27 DASD devices for TSM db, log, or backup/archive pool volumes? Thanks, in advance. Peter Glass MVS Storage Management -----------------------------------------------------------------------`