Re: Other computers HIGHLY degrading network performance (DoS?)

[Martin Josefsson]

On Fri, 26 Oct 2001, Anuradha Ratnaweera wrote:

> > One machine begins an intensive downloading job.  How can this degrade the
> > network performance even for ICMP packets between another machine and the
> > router?  Notice that this can't be collitions because the download goes at
> > 64kbps and the local network is 100 Mbps.  Something funny is going on to
> > stop other people's packets.
> 
> Just found out that this is _not_ a problem of the "download accelerator", but
> something to do with queuing algorithm of the router.  Even a normal wget
> process or a big mail has a big impart on the network.  Hopefully an iptables
> firewall would solve the problem.

I'd advice you to seriously look over your network, are you 100% sure you
don't have a duplex-issue anywhere?

I've been running linuxrouters for quite a while and right now I have a few
linuxrouters routing 100Mbit/s internetconnections. We have never had any
problems like the one you describe so my first guess would be that you
have a duplexproblem, probably between the linuxrouter and the switch it's
connected to on the inside, that's usually where it's located. Or maybe
between some switches or something but do look into this. I seriously
doubt that this a problem with the networking in linux.

/Martin

Never argue with an idiot. They drag you down to their level, then beat you with experience.