Re: Weird: eth0->adsl link becomes slow after 1 week running

From: Nils O. Selåsdal (
Date: 04/30/04

Date: Fri, 30 Apr 2004 09:20:43 +0200

On Thu, 29 Apr 2004 22:25:52 +0100, users wrote:

> Hi there,
> This is a very weird issue and took me a long time to realize that was
> happening.
> It seems that, when the system is up for more than aprox. 8 days, the
> outside interface (eth0->adsl) suddenly becomes terribly slow,
> until I restart the system. If I restart just the interface, it
> solves the problem for about 2 min, and then goes slow again (icmp
> replies from a near website decreases from 30ms to 2000ms in less
> than 1 min), even when the network is idle (empty nat/forward table
> and no packets going through eth0 or eth1). I tried almost
> everything, and I am preety sure its an internal issue (not
> adsl->isp), since tcpdump shows that the outgoing packets are
> actually taking some time to leave eth0 and hit the modem (the
> replies from the 'outside world' (adsl->eth0) are actually preety
> fast). I also tried renewing the lease, restarting the modem,
> restarting the whole network (same results as restarting just the
> interface), flushing/reloading firewall rules, setting very short
> masquerading timeouts, and many other things, but I just can't figure
> what is going on, or where, why, how.
> Right now the only "solution" I have is to reboot the system weekly
> from a cron job, but this is just very pfffffffff.....
> Note that, everything runs perfectly, until the system is up for more
> than 1 week.
> Then the issue occurs, and is only solved when the system is
> restarted.
> I1m running rh6 on a small network gateway, eth1=lan, eth0=internet.
If you really mean RH 6 here, please update it as it's very old, and
contains numerous security flaws.

Nils Olav Selåsdal
System Engineer
w w w . u t e l s y s t e m s . c o m