Re: What causes ORA-12547: TNS:lost contact ?

In <1154124884.512406.70700_at_m79g2000cwm.googlegroups.com> "joel garry" <joel-garry_at_home.com> writes:

>Stan Brown wrote:
>> Last night on an instance that has been up for over 100 days, and on a
>> machine with an uptime over 400 days (HP-UX 10.20 and Oracle 7.3.4.5.0,
>> I started getting :
>>
>> ERROR: ORA-12547: TNS:lost contact
>>
>> Intermitentaly on attempts to connect to the instance. I also got some
>> errors about TNS path? Sorry I don't have that one handy.
>>
>> From an OS perspective, the machine seems healthy (not out of process table
>> entries or anything like that, I don't believe).
>>
>> What should I look for to troubleshoot this problem?

>Figure out why processes are being given the boot-rear. This is almost
>certainly on the OS side. Ask on an hpux group why processes might
>suddenly have trouble starting up.
>Look in the syslog for symptoms of memory fragmentation. It could just
>be 400 days is too many. I know, I hate the MS-think about rebooting
>to fix problems, too.
>Check ps for zombies or large number of processes that shouldn't be
>there.
>How much swap space do you have, primary and secondary? You might have
>just tipped past a limit. Check listener.log for errors, too.
>Check $ORACLE_HOME/otrace/admin for big files (if you've accidentally
>turned on tracing, you could be expending lots of resources writing to
>here - I think it was 7.3.2 where they delivered this turned on!).
>Look for an environment variable called EPC_DISABLED and make sure it
>is true.
>netstat -a, see if something is not freeing ports. It could be that
>just a few things dying has cascaded into lots of things retrying while
>the tcp times out.
>Check hardware.
>Get hp support involved to use the tools to really dig into this.
>Upgrade to a supported database.

Thanks.

This somewhat confirms what I was suspecting.

I've already looked at the size of the process table vs maxprocs tuning in the kernel, and used Glance to look at almost everthing that it can display. Swap space is fine.

memory fragmentation I wiil try to figure out how to check.

Thanks, again.

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