View Full Version : How to know what wrong?

21st March 2005, 06:51 AM
I encounter problem that the machine got hang at aound 1:05 am everyday (I got this information from the /var/log/maillog. If I have a reboot of the system, it will be back to normal until the next day. How can I get more information on which programs caused the problem?
Is it related to cron job? But I have gone through these and seems none was working at this time frame.


21st March 2005, 09:34 AM
You can try looking at the system log file "/var/log/messages"......

Though for a process to die at the same time every day is highly unusual. Most software problems are "event" driven, ie: bad disk, memory problems, buffer overflows (uncommon but it happens), but these problems typically would NOT be dependant on a speciific time of day.

So in other words, it's probably not a process that is running throughout the day, but one that starts at 1:05 am everyday.......

and when you say your machine hangs, how does it hang??? get VERY slow for a moment? or locks up? self-reboots?, any mouse/console response at all? Could this be a DHCP problem where a lease is being renewed at the same time every day? (or an IP address changed?)

21st March 2005, 02:38 PM
The system hangs. Occasionally keyboard can input a few character but no repsonse.

I will check for DHCP problem as I notice that there is an unusual IP request for the DHCP server.

21st March 2005, 05:47 PM
another thought for you.

you can try leaving the machine with:

tail -f /var/log/messages

there's a cronlog file somewhere too, but I'm not sure of the name...check the /var/log directory.

If it hangs at 0105 AM, try leaving a window open with the tail -f <filename>

It will print the end of the file while scrolling new input placed at the end.

Read the file when it hangs, and you should have the problem, if you are looking at the log file that the problem is reported to.

24th March 2005, 02:07 PM
It seems to be due to dhcp problem.

Thank you for your advice.

24th March 2005, 02:10 PM
you are welcome.

DHCP hangs the machine- that does seem strange. Try setting static?

24th March 2005, 02:42 PM
It seems to be only possibility. No new program added Only updated on anti-virus signature for clamav.
log file has a DHCPNAK request.
I change all the IPs to static. Working for a day without problem.