Re: Login.template silly problem...

On Wed, 1 Oct 2008 19:09:38 +0000 (UTC), helbig@xxxxxxxxxxxxxxxxxxxxxxxx
(Phillip Helbig---remove CLOTHES to reply) wrote:

Anyway, defining these two commands should be removed from the template:
only in case of local attached terminal or LAT login they will work.
Most people either login through remote (telnet,ssh) or in a X11 session:
in those cases the shutdown or reboot will only start the shutdown and then
leave the system in an inconsistent state.

Actually, I have experience with a reboot via telnet. It worked several
times. Was I just lucky?

No, you weren't.

The shutdown procedure first creates your process tree, if any: i.e., if you
start shutdown from within a subprocess, it will create a list of PIDs
representing the hierarchy from that subprocess up to and including the
process created when you logged in. Then it will look for every process in the
system and stop it if it is running with a UIC greater than [1,*], and if its
name does not start with "DECW$", and if its name isn't "TCPIP$SSH_SSHD2", and
if its PID isn't present in the previously built process tree.

So, if you start shutdown from a telnet, ssh, DECwindows or DECnet connected
session, it should finish correctly because neither TCP/IP main process (which
run as [1,4]) nor ssh server or DECterm (because they are explicitly skipped)
will be killed along the way. DECnet will be put in shut (not off) state so to
disallow further activity without disrupting existing network links, and its
main processes run in group 1 (NETACP as [1,4], REMACP and NET$ACP as [1,3]).
LAT too does work the same because LATACP runs as [1,4] like many others.

Instead, if you submit SHUTDOWN.COM for batch processing, you'll be in trouble
because - well before the end of the procedure - it proceeds to stop all the
queues and all the queue managers, so it would kill itself leaving the system
in a weird state. To "batch" shutdown you must use a detached process as it
will be comprised in the above mentioned process tree, thus protecting itself.

Look for "job_tree" and "qman_name" in SHUTDOWN.COM and proceed from there.

HTH,
G.

.

Relevant Pages

  • Re: Login.template silly problem...
    ... only in case of local attached terminal or LAT login they will work. ... Most people either login through remote or in a X11 session: ... in those cases the shutdown or reboot will only start the shutdown and then ... SHUTDOWN from TELNET and SSH work fine; ...
    (comp.os.vms)
  • Re: Login.template silly problem...
    ... only in case of local attached terminal or LAT login they will work. ... Most people either login through remote or in a X11 session: ... in those cases the shutdown or reboot will only start the shutdown and then ... I have experience with a reboot via telnet. ...
    (comp.os.vms)
  • Re: Login.template silly problem...
    ... about that and about historical variance of shutdown procedure ... Whatever was the reason to change the template, in my opinion both do it ... YES for SHUTDOWN, NO for REBOOT. ... only in case of local attached terminal or LAT login they will work. ...
    (comp.os.vms)