From:	CSBVAX::CSBVAX::MRGATE::"SMTP::CRVAX.SRI.COM::RELAY-INFO-VAX"  3-DEC-1988 12:05
To:	MRGATE::"ARISIA::EVERHART"
Subj:	Mom$Load logical name and VMS 5.0


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Date: Wed, 30 Nov 88 09:32 PST
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From: Chris Yoder <CHRIS%YMIR.BITNET@CUNYVM.CUNY.EDU>
Subject: Mom$Load logical name and VMS 5.0
To: info-vax@kl.sri.com
X-VMS-To: INFO-VAX-SUBMIT

[Bug Poison]

     For those of you who haven't gone to VMS 5.0 yet and who use your system
as a load host for DECservers, I have discovered the following gotcha...  If
you define MOM$LOAD as suggested in either the DECserver 100 or DECserver 200
manual *BEFORE* you execute SYS$MANAGER:STARTNET.COM to bring up DECnet,
Mom$Load will be defined in such a way that none of your DECservers will load.

     What happens is this: as of VMS 5.0, STARTNET.COM checks to make sure that
the logical name MOM$LOAD either doesn't exist or if it does exist has only one
element in it.  If either condition is true, then STARTNET doesn't try to
define Mom$Load, however, if the condition is false it defines Mom$Load to
point to Mom$System unconditionally (this to make certain that MOM$LOAD is
defined "correctly").

     The DECserver 100 manual suggests defining MOM$LOAD to be
SYS$SYSROOT:[DECSERVER], (which is flat-out wrong) and the DECserver 200 manual
suggests defining MOM$LOAD to be the current definition of MOM$LOAD +
SYS$SYSROOT:[DECSERVER].  The DECserver 200 manual is correct, as long as you
make the definition *AFTER* STARTNET.COM is run...  If you want to make the
definition before you use STARTNET.COM, then define MOM$LOAD to be [the current
definition of MOM$LOAD,] SYS$COMMON:[MOM$SYSTEM],SYS$SYSROOT:[DECSERVER].

     Since some of us like to make sure that the system has all of the logical
names defined before starting up any networks, this one can be a real head-
banger...  I only found it because I wasn't totally familiar with the system
that was having the problem and simply did a ``SEARCH SYS$MANAGER:*.COM
MOM$LOAD'' and found out that STARTNET was playing with it!

-- Chris Yoder                               Chris@Ymir.Claremont.Edu
     Harvey Mudd College        Bitnet ----- Chris@Ymir