Kris,
thanks for your explanation. I have now sucessfully created my 2nd GCS
segment GCS2 with the group member GCS2 ASSEMBLE
CONFIG SYSNAME=GCS2, X
RECVM=GCS2, X
DUMPVM=MAINT, X
MAXVM=5
AUTHUSER START
AUTHUSER NAME=GCS2
AUTHUSER NAME=MAINT
AUTHUSER NAME=VTAM2
AUTHUSER END
RESSTOR START
RESSTOR END
SEGMENT START
SEGMENT NAME=VTAM
SEGMENT END
END
The GCS2 userid started successfully with IPL GCS2. Now I will setup the
VTAM2 userid (ATCSTRxx, CDRM etc.). This should be no problem with IPL GCS2.
Again thanks for your help.
kind regards
Franz Josef Pohlen
Am 19.10.2010 10:45, schrieb Kris Buelens:
The GCS segment must be unique indeed, it contains SW type storage (that
is Shared Write). And access to that SW storage need to be
"controlled". GCS has mechanisms to make it possible to avoid programs
stepping on each-other. But, these mechanisms provided integrity in a
single GCS group. The GCS "Recovery machine" is part of that machanism.
So, new GCS group means: new GCS NSS and a new GCS recovery machine.
The SW section also makes that a GCS is saved with CLASS R, Restricted,
meaning that to use it one needs to be authorised with a NAMESAVE
statement in the directory. Otherwise any VM user could issue IPL GCS
and start storing things in the SW area, effectively killing VTAM's
environment.
The VTAM (and maybe NETVIEW) segments are all SR, Shared Read, meaning
all users use the same pages, but they cannot modify (CP and the HW take
care of enforcing that). So, one copy is always enough.
To be more complete, saved segments can also have EW, Exclusive Read,
storage areas, meaning that each user gets it own copy of these
section(s). This is the case for CMS, GCS, CMSAMS and CMSVSAM.
Exclusive, so no sharing problems and one NSS copy is enough.
2010/10/19 Franz Josef Pohlen <[email protected]
<mailto:[email protected]>>
Thanks Kris,
I didn't know that 2 VTAMs can use the same VTAM DCSS concurrently.
Will there be no storage problem if the number of defined LUs
increases with the 2nd VTAM or is this possible problem only related
to the GCS segment which I will rebuild as a GCS2 segment and user.
kind regards
Franz Josef Pohlen
Am 19.10.2010 09:48, schrieb Kris Buelens:
I don't see any need/benefit to create another VTAM saved segment
(guessing both VTAMs will use the same VTAM SW level). Having both
VTAMs use the same segment even saves some real storage, so why
do you
say "to avoid any storage complaints"?
The VTAM segment can even fall inside the DEF STORAGE of the VTAM
machine (as it does in the default setup): the name of the VTAM
SEGMENT
is listed in the GCS definitions, meaning GCS will load it soon
after
its IPL, and this for all members of thje GCS group, not only
for user VTAM.
If however you really insist:
Q NSS NAME VTAM MAP to get the addresses it currently uses
DEFSEG VTAM2 xxx-yyy SR where xxx-yyy is obtained from Q NSS
run the VTAMSEG EXEC
This is outside the VMSES environment, so if you'd apply service to
VTAM, you'll have to repeat the above.
2010/10/19 Franz Josef Pohlen <[email protected]
<mailto:[email protected]>
<mailto:[email protected] <mailto:[email protected]>>>
Hi listers,
my customer uses VM-TN3270E, SCEXIT and Dial to VM-VTAM to
connect
to his CICS-TS in zVSE. Now he is going to reach the 4096
devices
limit in his vm-vtam, because the Non-SNA resources support only
3-digit device numbers. We want to create a 2nd GCS and VTAM
with
its own segments to avoid any storage complaints. I know how to
build a new GCS, but how can I build a new VTAM NSS VTAM2
instead of
VTAM.
--
kind regards
Franz Josef Pohlen
--
Kris Buelens,
IBM Belgium, VM customer support
--
Kris Buelens,
IBM Belgium, VM customer support
