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Home -> Community -> Usenet -> c.d.o.server -> Re: What causes ORA-12547: TNS:lost contact ?
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.
jg
-- @home.com is bogus. http://www.crystalinks.com/shc.htmlReceived on Fri Jul 28 2006 - 17:14:44 CDT