Hi all,
Thanks for your help and here is SUMMARY:
Mine question:
> Jan,
>
> > I'm running DU V4.0E. I'm trying to find out how to convince qmaster and
> > dqs_execd to be restarted after rebooting of the system. I've tried
> > simply include it in the inittab but it didn't work
> > (dqs_execd:23:wait:/sbin/dqs_execd > /dev/console 2>&1). Wouldn't be
> > better to include it in crontab?
>
One of the answers:
> The normal facility for doing this is to use the runlevel scripts. These
> scripts are run whenever the system alters it's runlevel -- like at
> startup and shutdown.*
>
> * Shutdown is a special case for Tru64 prior to 5.x. The "-r" and "-h"
> switches would simply kill all processes rather than running the
> runlevel trasition scripts. With 5.x a "-s" flag was added to allow
> shutdown to run the scripts with the "-h" and "-r" switches. A shutodwn
> without any switches has always used the scripts to bring the system
> down to single-user mode.
>
> The design is a little odd before you get used to it.
>
> /sbin/init.d
>
> This is the directory where the scripts are actually located. The
> normal design of the script it to have a case statment that handles
> the command line paremeters passed to the script. The scripts
> should always handle "start" and "stop", but other commands like
> "status" and "restart" are oftern implemented.
>
> This is where your script to start or stop DQS services should go.
> When the script is run as "/sbin/init.d/scriptname start" it should
> start the DQS services. Conversely, when run with "stop" it should
> stop the services. Take a look at the scripts in /sbin/init.d for
> ideas.
>
> /sbin/rc0.d
> /sbin/rc2.d
> /sbin/rc3.d
>
> These are the runlevel directories. These directories generally
> contain symbolic links back to scripts in the /sbin/init.d
> directory. By convention, files in these directories begin with
> either the letter "S" or the letter "K" and are followed by a
> two-digit number and a filename.
>
> From the rc3.d manual page:
>
> In general, the system starts commands that begin with the letter
> "S" and stops commands that begin with the letter "K." Commands that
> begin with the letter "K" run only when the system is changing run
> levels from a higher to a lower level. Commands that begin with the
> letter "S" run in all cases. The numbering of commands in the
> /sbin/rc3.d directory is important since the numbers are sorted and
> the commands are run in ascending order.
>
> Clear as mud right?
>
> Here's what happens when you boot (simplified):
>
> 1. The system boots.
>
> 2. The root filesystem is mounted.
>
> 3. Init is started.
>
> 4. Init scans /etc/inittab, looking for the initdefault keyword. This is
> normally "3" on Tru64 systems. If the entry is there, the init process
> runs all tasks at that runlevel in the inittab file. One of these
> will be /sbin/rc3. The runlevel is the second field in the inittab.
> The runlevels are single digits, so "23" means to run for both "2"
> and "3".
>
> 5. The /sbin/rc3 script runs all of the programs in the /sbin/rc3.d
> directory that start with "S" in accending order (S01file, S01file,
> etc.). The scripts are passed the parementer "start".
>
> Shutdowns, using the runlevel scripts are similar:
>
> 1. The super-user signals the system to shutdown (halt).
>
> 2. Init runs all of the init level 0 stuff in the inittab file.
> This includes the /sbin/rc.0 script.
>
> 3. The /sbin/rc.0 script runs all of the scripts in /sbin/rc0.d
> that start with "K", these scripts are passed the paremeter
> "stop". The script then runs all of the scripts in the
> directory that start with "S", passing them "start".
>
> The reason for all of this is to create a system that would allow
> the admin to have a system that can be brought up in various modes.
>
> Traditionally these were:
>
> 0. Shutdown, halt.
>
> 1 or S. Single user
>
> 2. Multi-user, no network services.
>
> 3. Multi-user with network services.
>
> 4. Undefined, usually 3 with major services (i.e. web, database, etc.).
>
> 5. Undefined, used by some vendors for multi-user with network services
> with xdm running on the console.
>
> 6. Shutdown, reboot.
>
> The idea is that if you need to do maintenance on the system without
> having users underfoot, you would go to runlevel 2 and kill off the
> network services.
>
> The long and short of this is:
>
> 1. Write a script that starts and stops the DQS services, as discussed
> above. Use the other scripts in /sbin/init.d as examples. Call the
> script something like dqs.
>
> 2. Make the symlinks:
>
> ln -s /sbin/init.d/dqs /sbin/rc0.d/K01dqs
> ln -s /sbin/init.d/dqs /sbin/rc2.d/K01dqs
> ln -s /sbin/init.d/dqs /sbin/rc3.d/S87dqs
>
> 3. Try rebooting the system. If you do a shutdown (without "-h" or
> "-r") to bring the system down to single user and then reboot,
> dqs should shutdown and startup with the system.
>
> Good luck,
>
> Tom
> --
Received on Tue Jan 23 2001 - 10:51:43 NZDT