Hello managers,
I have received seven replies to my question from:
Russel Morison <russel_at_maths.unsw.EDU.AU>
Lucio Chiappetti <lucio_at_ifctr.mi.cnr.it>
lombardi emanuele <lele_at_mantegna.casaccia.enea.it>
Peter Stern <peter_at_wiscpa.weizmann.ac.il>
George Guethlein <GGuethlein_at_GiantOfMaryland.com>
"Rustam T. Usmanov" <rustam_at_stu.ruslan.ru>
"Thomas M. Payerle" <payerle_at_physics.umd.edu>
Thanks to all of you.
The consensus is that "shutdown -h" brings the system to console (it's the
essential addition to what I can see on page 1-3 of Customer Technical
Information).
Some possible "annoying results" of setting AUTO_ACTION = RESTART are
following.
Lucio Chiappetti wrote:
"I believe the only problem is that if you experience a blackout, and
have "restart" set, the machine will reboot once power is back. If then
power is unstable and is lost while booting, you may get corruption on
the disks (e.g. during the fsck phase).
So we've set all our machines to "HALT".
Actually now we've bought UPSs (Uninterruptible Power Supplies, essentially
a buffer battery), so we could perhaps relax this. Smarter UPSs can be
programmed to shutdown the machine via a serial connection after so many
minutes from blackout, and to turn it on when power is back, AND the
battery is so much percent full (so that a clean shutdown can occur)."
George Guethlein uses "auto_action=restart" on ALL his systems
(2100, 4100's and 8400) running DEC Unix. But he had 1 BAD situation with it
when a core dump (after Informix database crashed) filled up the "/" file
system, and auto reboot failed because "/" was full (system crash), and so on
(20+ times!). To prevent such things, he just made sure that no applications
write (dump) to the "/" and has not had the problem ever again.
Russel Morison mentions a little "trick" to prevent undesirable reboot:
"... when you have AUTO_ACTION=restart and you do a shutdown -h now
the machines shuts down to the console mode. If you power the machine off ,
and power it back on again the machine will try to auutomatically boot into
the operating system. If you want to stop it booting into the operating
system a few control C's at the end of the harware check, just before it
boots up the kernel normally does the job."
From some letters of other managers I can suppose that the startup actions
for different DEC system models are different.
My original message is beneath.
Thanks again,
Irene
==============================================================================
Hello managers (and somebody of DEC people I hope),
I know it's HALT always recommended. Newertheless I have a heavy motivation
to reboot the system automatically in the case of crash while keeping the
possibility to enter in console when I need (executing shutdown -h or init 0
for example). In the documentation I didn't see a definite answer whether
the purpose is achieved with setting AUTO_ACTION = RESTART. Besides, I have
looked through all (eight) messages in the archive concerning RESTART action
but yet didn't find what I need.
I'm thinking over setting AUTO_ACTION = RESTART for our old DEC 2000 model
300 having experienced four crashes - by two different reasons (as far as
I can judge by appearances of the stack in crash-data, inevitable with "kernel
memory fault"). I perceive that RESTART may be considered only as a palliative,
nevertheless I have to minimize the inconvenience for our users in the case of
the system crash.
So, I see in Customer Technical Information:
5-12:
RESTART The system boots automatically when it is turned on or after it fails.
(It's all).
1-3:
The system enters and remains in the Open VMS and OSF/1 console under the
following conditions:
- When AUTO_ACTION is set to HALT and OS_TYPE is set either to VMS or to OSF.
- When power-up tests fail.
(No other opportunities pointed).
From 5-12 I can conclude that under AUTO_ACTION = RESTART after crash the
system reboots. Meanwhile I want after shutdown -h the system to enter (and
remain) in console but from 1-3 it follows (the first part of the first
condition is false) that I get to console only if tests fail.
So, what I get executing shutdown -h? (I wouldn't like to investigate it in
such experimenting, especially when the result is unpredictable. Eventually,
it's the documentation that should say it).
The system is 3.2c, DEC 2000 model 300.
What annoying result does RESTART imply?
Thanks,
Irene
Novosibirsk, Russia.
Received on Thu Jun 04 1998 - 06:43:01 NZST