David,

 Somebody is selling you a bill of goods.  We have all of our clients point
to a specific MVS server by using a TCP/IP alias (or cname in DNS-speak).
If one of our MVS LPARs goes down we have the option of bringing the server
up on another LPAR and then have the DNS entries modified.  It works just
fine.

Good luck,
Dan T.

----------
> From: Sanders, David <DSanders AT INTERNAL.MASSMUTUAL DOT COM>
> From: Sanders, David <DSanders AT INTERNAL.MASSMUTUAL DOT COM>
> To: ADSM-L AT VM.MARIST DOT EDU
> Subject: Moving the server, transparently
> Date: Tuesday, December 30, 1997 6:10 AM
>
> We currently have our server running on a MVS mainframe, and I want to
> move it to another mainframe.  In anticipation of that, I had requested
> all of the client administrators to change their options for
> TCPSERVERADDRESS from either an old logical name "mvs.mm.com" for
> example or a hard-coded TCP address to a NEW logical name.  My purpose
> was so that once all clients had made the change, the new logical name
> could be switched from MVS system to another MVS system, simply by
> having the TCP/IP gurus changing the resolve of that name from one TCP
> address to another.  Well, I'm now told that this is not do-able.  How
> have other folks done this??