msgbuf file

[augusto cossa]

Good Day,

I'm facing a problem concerning /var/adm/msgbuf file. Everyday I trim this file to 10% but in a caple of seconds becomes the same size. The soze that have now is:

Percent Full Current size Recommended size
400 4100 1024

Other thing is, how can I see the number of files opened by all proccess and if I increase the nfile it's needed to increase the nproc?

Thanks,

A Cossa

[Philip Chan_1]

For number of open files try

sar -v 2 9

second last column of the output should be what you're looking for.

Rgds,
Philip

[CHRIS_ANORUO]

You can download and install lsof from the hp software porting site with this link:http://hpux.cs.utah.edu/hppd/hpux/Sysadmin/lsof-4.48/

If you increase MAXUSERS it will increase NFILE and NPROC parameters.

[CHRIS_ANORUO]

Augusto,

To add to the above, the msgbuf is generated from dmesg output. Use dmesg to check if there are errors reported in your system.

Cheers!

[augusto cossa]

Hi Chris,

I have chacked the dmesg and the output is as followed:
strings /sbin/dmesg
$Revision: 92453-07 linker linker crt0.o A.10.44 951205 $
/usr/lib/dld.sl
ERROR: mmap failed for dld
@(#) $Revision: 72.1 $
msgbuf
/var/adm/msgbuf
Can't open /var/adm/msgbuf
/stand/vmunix
Can't get kernel namelist
/dev/kmem
Can't read kernel memory

What have I to do?

Your help will be appreciated,
Thanks

A Cossa

[Ruediger Noack]

Hi,

have you created a new kernel since last boot and placed it at /stand/vmunix ?

Ruediger

[CHRIS_ANORUO]

First the perms on the file should be 644, owned by root, group sys.
Then retune the kernel by increasing MAXUSERS by 50. This is just too increase NFILE and NPROC for you as per 1st questn. Relink the kernel and system will be rebooted.
These steps will help you clear the last dmesg error messages and stabilize your system.

Find time to do this!

Cheers!

[Kofi ARTHIABAH]

Hi Augusto:

What Chris was refering to about running dmes is that you should actually type the command dmesg at the prompt:

#dmesg

you can also check your /var/adm/syslog/syslog.log for any errors that are causing your msgbuf to grow

[Gail MacDonald]

Add the "-" option on the /usr/sbin/dmesg command in the cron job that appends to your /var/adm/dmesg file. See man page for dmesg.

The effect of this is to only append messages that it hasn't reported before, rather than the same messages over and over.

[Bill Hassell]

Check root's crontab entry (crontab -l) and see if you are running dmesg into this file. If so, here are two recommendations:

1. Change the name of the file to dmesg.log so it makes sense. msgbuf or messages simply doesn't tell you how the log file is being created.

2. Run the cron job every 10 minutes but be absolutely sure tha the command looks like:

10,20,30,40,50 * * * * /usr/sbin/dmesg - >> /var/adm/dmesg.log

Notice the - sign which keeps dmesg output limited to only that which has changed since the last invocation.

And of course, look at the end of the log file to see if there is an important series of messages like: / filesystem is full