SAP not starting up

[AL_3001]

Hi Friends,

Attaching o/p of Memlimits as mentioned by Hein van den Heuvel....

I see a few failures at the end of the logs...

Kindly advise....

[Hein van den Heuvel]

From output....

>> Maximum protectable size (mprotect)..: 176 MB

So that would explain the reported:

>> 205748 kilo bytes of shared memory for PXA not available.

Now as to WHY?

Back to an earlier question:
Are you using 32-bit products?
What HPUX version?

You may be limited to 1.75 GB total shmmax
Give too much to Oracle, and none is left fro SAP.

Or it could possibly be the system tuning setting shmmax itself.

Check out the 'readme' in ftp://hprc.external.hp.com/sysadmin/programs/shminfo/

For yet an other tool check: Dave Olker's reply in:
http://forums11.itrc.hp.com/service/forums/questionanswer.do?threadId=1048211

Also:
http://unix.derkeiler.com/Mailing-Lists/HP-UX-Admin/2005-05/0020.html

Hope this helps some,
Hein van den Heuvel (at gmail dot com)
HvdH Performance Consulting

[Eric Antunes]

Hi Hein,

I know it because after Ashish said SAP script couldn't start the instance and posted the "ipcs -ma" output, I saw this line:

m 519 0x91246e28 --rw-rw---- orarsp dba orarsp dba 54 1064181760 8514 23662 6:09:52 6:10:00
2:23:07

This is the Oracle instance still in memory, so it wasn't shut down properly and, thus, Oracle RDBMS won't be able to start it.

About the serve restart, in the 2 ou 3 similar situations I had, I found it to be faster than trying to remove those active segments from memory...

Best Regards,

Eric Antunes

[Hein van den Heuvel]

Eric, I saw the orcacle segment CTIME being 2:23:07, followed by some sapsys owned segments with CTIME 2:23:21.
So I read that as Oracle having been started as a step in the failing sapstart, not as a leftover from a previous run.


Ashish, Has that SAP instance been down for all this time? I kinda hate to suggest this, but you might as well hit 'the big red button'... try a reboot?
"re-boot macht immer gut"

Hein.

[AL_3001]

Hi Hein Van Den,

It is a 64 bit application and HP-UX version is 11.00.


Cheers,
Ashish

[AL_3001]

Hello,

Some more information:

Recently the application team had shutdown the application as unix had to carry out disk replacement activity.

When they tried to start SAP/Oracle through script it started in unstable state with PXA errors.

They tried to start sap/oracle again but the same PXA errors occured.

Tried to start sap/oracle through standard SAO commands, SAP started with the same pxa errors. The cleanipc command failed to resolve the issue (as told to us)

Application team asked us to reboot the server, and than the application team started the sap/oracle through script and the system started fine.

Is it that the memory is not getting released when the application is stopped?

How to overcome this issue, so as to the memory is deallocated.

Thanks.

Regards,
Ashish

[Bart Paulusse]

Hi Ashis,

if Oracle and SAP startup fine after a system reboot, but not after a stop of Oracle and SAP, then it looks as if there is a problem with the stop script.
Does the script wait for the stop commands to complete?
Does the start script wait for the stopscript to complete?

could you perhaps post both scripts?

[Eric Antunes]

Hi Ashish,

" Is it that the memory is not getting released when the application is stopped? "

Yes, and the active shared memory segment is not deactivated because the shutdown command wasn't successful (script's return code not equal to 0). That can happen for several reason that you or your DBA must investigate.

Best Regards,

Eric Antunes

[Yogeeraj_1]

hi,

Allow me to also add that the database alert.log can also shed some lights on the exact problem. (in case it is related to the database itself)

hope this helps too!
kind regards
yogeeraj

[AL_3001]

Friends,

We will be carrying out the activity to stop/start sap/oracle this weekend to find the root cause without the need to reboot the server.

I am quite confident that the shared memory is not getting released when the DB is stopped. The reason behind this is, when we tried to start it, we got PXA shared memory error, but when the server was rebooted and oracle/sap was started, it started normally without any error. This tells me, the problem is wih the memory not releasing.

During the activity, the basis team will be stopping the application. Once it is done, we (unix team) will check the shared memory (ipcs -m) to see if the shared memory is released or not. If it has not, we will remove it using ipcrm -m and than ask basis team to start the application.

My question is, if it is problem with releasing of shared memory, how can we overcome it as it will not be possible to manually release the memory everytime.

Thank You.

Regards,
Ashish