topic Re: Neighbour overflow error in Operating System - Linux

Neighbour overflow error

sacthivel.C — Wed, 18 Feb 2009 05:30:16 GMT

Dear all,
We are using Redhathat Linux 9 server.
(Linux server.cenkapune.com 2.4.20-8 #1 Thu Mar 13 17:54:28 EST 2003 i686 i686 i3
86 GNU/Linux) with sendmail configured in it.
From the last week onwards the "neighbour overflow error" error comes on the server console continuously and the server get isolated from the network.It is not pinging.
As per some documents searched from Google i executed the following commands.
# /sbin/sysctl -w net.ipv4.neigh.default.gc_thresh3 = 4096
# /sbin/sysctl -w net.ipv4.neigh.default.gc_thresh2 = 2048
# /sbin/sysctl -w net.ipv4.neigh.default.gc_thresh1 = 1024
#ip route flush cache

But it worked only for one day and from the next day onwards it starts giving the same error.
I attached here the /var/log/messages file also.(pls open it in wordpad).
I didn't have that much idea in Linux.Would somebody help me?

Re: Neighbour overflow error

Vitaly Karasik_1 — Wed, 18 Feb 2009 08:21:32 GMT

I suggest to upgrade to some recent distribution; it seems like a kernel bug.

Re: Neighbour overflow error

Vitaly Karasik_1 — Wed, 18 Feb 2009 08:38:59 GMT

And even for RHL9 (if you have to stay with it) I suggest to upgrade kernel - seems like kernel-2.4.20-31 was the latest.

Re: Neighbour overflow error

sacthivel.C — Wed, 18 Feb 2009 11:43:26 GMT

would you pls tell me the procedure and the precautions to take?
Because it is our web server

Regards,
C.Sacthivel

Re: Neighbour overflow error

Vitaly Karasik_1 — Wed, 18 Feb 2009 13:30:28 GMT

As for upgrade to recent distro - it's no trivial - you should write down all custom program and configurations, install new system and apply your configs.

But installing new kernel should be straitforward -
1) rpm -iv ftp://ftp.freshrpms.net/pub/updates/redhat-9-i386/kernel-2.4.20-31.9.i586.rpm

(or from other mirror - see http://rpm.pbone.net/index.php3/stat/4/idpl/2411501/com/kernel-2.4.20-31.9.i586.rpm.html)

2) reboot and during boot grub screen choose this kernel

3) if everything is OK, edit /etc/grub.conf - put the new kernel as default