topic Re: Init Run Levels in Operating System - HP-UX

Init Run Levels

devshlom — Mon, 23 Jun 2008 06:57:30 GMT

Hi guys,

During installation I will have to install a service.
1. Can you give me a quick overview about the run-levels on HPUX 11.23 PARisc?
2. How do I create the S/K links on /sbin/rcX.d? is there any command for that, as the chkconfig on linux or create a soft link via "ln"?
3. Do you have a good HP documentation link for this subject?

tx.

Re: Init Run Levels

Venkatesh BL — Mon, 23 Jun 2008 07:01:40 GMT

Have a look at:
http://forums12.itrc.hp.com/service/forums/questionanswer.do?&threadId=1042729

http://docs.hp.com/en/B9106-90008/init.1M.html

Re: Init Run Levels

Mustafa Gulercan — Mon, 23 Jun 2008 07:13:32 GMT

hi;

read the man page.
# man rc

regards,
mustafa

Re: Init Run Levels

Kenan Erdey — Mon, 23 Jun 2008 07:16:37 GMT

Hi,

run level directories contains scripts that will run while start up, while changing run levels ( up or down) or shutting down. While going down from rc3 to rc1 K scripts run, while going up from s1 to s3 S scripts run. S is for starting, K is for killing.

/sbin/init.d/ director is your directory where you'll put your script for start and kill. And the synax is below:

#!/sbin/sh

case "$1" in
start_msg)
echo "Start "
;;

stop_msg)
echo "Stop "
;;

'start')

;;
'stop')
# Stop the oracle databases

;;
esac

and after you should create links for Rc directories. change with appropriate file names. And also you may change run levels in which the service will be started and killed.

ln -s /sbin/init.d/ /sbin/rc3.d/S999

ln -s /sbin/init.d/ /sbin/rc3.d/K999

Kenan.

Re: Init Run Levels

Dennis Handly — Mon, 23 Jun 2008 07:48:57 GMT

>Kenan: And also you may change run levels in which the service will be started and killed.
ln -s ... /sbin/rc3.d/S999
ln -s ... /sbin/rc3.d/K999

Typically these numbers add to 1000, so that they are done in reverse order.

Re: Init Run Levels

devshlom — Mon, 23 Jun 2008 09:11:59 GMT

hi,

I wonder about those numbers... (Knnn/Snnn)
As I saw and also as dennis said, these number will complete to 1000.
For all the UNIX I know, the complition it to 100.

so,
1. are the lower number reserved for something?
2. what is the reason for these higer number?
3. if I have a service that for all the other UNIXes started at 91 and killed on 09 - what numbers you suggest me to set?

tx

Re: Init Run Levels

devshlom — Mon, 23 Jun 2008 09:15:51 GMT

and another important questions
1. if my service uses networking - basically I can start it on level 2 - don't I?
2. it this acceptable to do so?
3. I saw that most of the sevices/daemons don't have a kill script on level 0 - what should happen on system shutdown? (should I put K links on level 0, 1?

tx again

Re: Init Run Levels

Dennis Handly — Mon, 23 Jun 2008 09:29:31 GMT

>1. are the lower number reserved for something?

No, except they are done first.

>2. what is the reason for these higher number?

The range from 000 to 999? For more choices.
Note these numbers are an illusion. The scripts are done in ascii order and the reverse.

>3. if I have a service that for all the other UNIXes started at 91 and killed on 09 - what numbers you suggest me to set?

Probably 901 and 009.

>1. if my service uses networking - basically I can start it on level 2 - don't I?

You have to order it after the networking starts.

Re: Init Run Levels

devshlom — Mon, 23 Jun 2008 10:03:08 GMT

what about level 0 and 1?
should I put K link there?

Re: Init Run Levels

devshlom — Mon, 23 Jun 2008 10:11:32 GMT

one more:

What about the fact that when I reboot the machine I don't see my product in the printed down list:
XXX daemon was stopped.........OK
bla bla is down................OK

should I do something specific in order to get in this list?

Re: Init Run Levels

Dennis Handly — Mon, 23 Jun 2008 10:41:08 GMT

>what about level 0 and 1? should I put K link there?

rc(1M) says that S is at rcN.d and K is at rcN-1.d.

>What about the fact that when I reboot the machine I don't see my product in the printed down list: should I do something specific in order to get in this list?

Do you have start_msg & stop_msg entry as Kenan mentions?

Re: Init Run Levels

devshlom — Mon, 23 Jun 2008 11:03:55 GMT

>Do you have start_msg & stop_msg entry as Kenan mentions?

I don't use these names? should I? I have functions "stop" and "start"...

by the way.
I didn't understant the issue with init script:
If I want my service to be started for level 3 and above and be down for level 2 and below, where should I put my links? because somehow, when I'm on level 3 and I moved to level 4 with "init 4" the system runs my S link from rc4.d and fails.
shouldn't it recognize the the service is already up? should I remove the S link from rc4.d?

tx

Re: Init Run Levels

James R. Ferguson — Mon, 23 Jun 2008 11:06:20 GMT

Hi:

The manpages for 'rc(1M)' and the original 10.0 whitepaper on system startup scripts (which *still* applies today) provide a complete overview of the requirements you should meet.

The "rule of 1000" as mentioned, the difference betweent the number assigned to a start script and a kill script is discussed.

Use '/sbin/init.d/template' as a starting model for any script you write. In this way, you will follow the essential rules noted in the documentation.

http://docs.hp.com/en/934/startup.pdf

http://docs.hp.com/en/B2355-60130/rc.1M.html

Regards!

...JRF...

Re: Init Run Levels

devshlom — Mon, 23 Jun 2008 12:19:21 GMT

1. I can go with this template but am I required to?
I already have a file that works on all the other platform. Can I make it work with minimal changes?

Re: Init Run Levels

James R. Ferguson — Mon, 23 Jun 2008 12:28:05 GMT

Hi (again):

> I can go with this template but am I required to? I already have a file that works on all the other platform. Can I make it work with minimal changes?

You are *not* required to use the template, but you *are* required to follow the same logic. This logic is also discussed in the aforementioned documentation I cited.

Regards!

...JRF...

Re: Init Run Levels

devshlom — Mon, 23 Jun 2008 12:51:48 GMT

of course same logic!!!

but,
will it be acceptable to use a script that doesn't have "stop_message" and "start_message" for example (and "start_proc" instead "start")

do I have to use the rc.config.d/xxx file?

tx

Re: Init Run Levels

James R. Ferguson — Mon, 23 Jun 2008 13:30:57 GMT

Hi (again):

> but, will it be acceptable to use a script that doesn't have "stop_message" and "start_message" for example (and "start_proc" instead "start")

NO. You need to look at the documentation and the 'template' logic. These requirements are clearly documented. If you want your script to participate in startup and shutdown in HP-UX then follow the HP-UX guidelines!

You are making this much more difficult than it needs to be.

> do I have to use the rc.config.d/xxx file?

This is somewhat optional. However, by declaring variables in a file in '/etc/rc.config.d/' you can easily disable your startup and shutdown script without having to unlink the 'sbin/rc?.d' files from the '/sbin/init.d/' script. Look at '/etc/rc.config.d/mailservs' and '/sbin/init.d/sendmail' for one example of this mechanism.

Regards!

...JRF...

Re: Init Run Levels

devshlom — Mon, 23 Jun 2008 14:04:40 GMT

ok man,
I understand that.

let me give you the following scenario:
I have script on /sbin/init.d
S link on rc3
K link on rc2

If I run /sbin/init.d/my_s start twice, in the second time, I failed with the msg that the service is alreay up.

BUT,
if I move from level 3 to level 2 (the service is still up), and if I move from level 2 to 3, the sys tries to start the service again and it gets error msg from service - but not from the script as I expected.
How can I avoid that?
Why the script doesn't avoid this case?

tx

Re: Init Run Levels

James R. Ferguson — Mon, 23 Jun 2008 14:18:34 GMT

Hi (again):

> If I run /sbin/init.d/my_s start twice, in the second time, I failed with the msg that the service is alreay up.

Yes, that would be expected. You have done nothing to stop (kill) the first instance.

> BUT, if I move from level 3 to level 2 (the service is still up), and if I move from level 2 to 3, the sys tries to start the service again and it gets error msg from service - but not from the script as I expected.

Then your shutdown ("K"ill) script failed to stop the first instance of your process.

There are any number of good examples if you look at the scripts in the '/sbin/init.d' directory.

Regards!

...JRF...

Re: Init Run Levels

devshlom — Mon, 23 Jun 2008 14:49:24 GMT

Hi dude,

In my script, before starting it, I check that the service is yet up!
if it's up, I print the msg that the service is alreay started.
According to documentation (if I got it right) when I have S script on level 3 and K script on level 2, when I move from level 3 to 2, the Kill script on rc2.d shouldn't be invoked (only the K scripts from level 3)
that's why the service is still up when I moved from 3 to 2.
you understand my problem here?

also, I will look at more examples, but if you have some enlighment I will be happy to hear.

tx