Re: MTU problem with 2.0.26?

Hugo Van den Berg (
Wed, 27 Nov 1996 11:12:48 +0100 (MET)

On Tue, 26 Nov 1996, Ronan Mullally wrote:

> I upgraded 3 WWW cache servers from 2.0.24 to 2.0.26 yesterday. In the
> process I changed their ethernet cards from 3c590s to 3c905s running at
> 10Mbps (I'm using the current 3c59x driver from
> We have a frame relay network which doesn't like an MTU larger than 1006
> bytes, since upgrading the servers people have been having problems
> connecting to them, getting as far as 'host contacted, waiting for reply',
> then nothing. A packet trace shows the TCP session being opened then
> hanging. I've come across this in the past and over-size packets are
> the culprit.
> I ifconfig'd the mtu on the ethernet interfaces to 1006 and the problem
> disappeared, however the rest of our servers (2.0.24, 2.0.25 and Solaris)
> all use an ethernet MTU of 1500 without any problems.

I have 2 905's back to back running 3c59x 0.28c. After some initial
problems I got them working, with MTU's of 1500. One of them is using
2.0.26, the other 2.0.25 (and windoze).

> Has anything changed in the network code (fragmentation?) for 2.0.26 which
> would cause this to happen, or would the 3c905 be at fault?
> --
> Ronan Mullally 'In the Beginning there was
> Network Manager nothing, which exploded.'
> Ireland On-Line -- Terry Pratchett.