Excessive Collisions After FC1 Installation

[Scot L. Harris]

On Wed, 2004-07-28 at 11:38, Christopher A. Smith wrote:
> I recently installed FC1 (still a little wary of FC2) on a workstation and
> a laptop.  Both had previously been running RH 9; FC1 was installed by
> paving the hard drive and installing from scratch.  Immediately after the
> upgrade, I noticed a surge in Ethernet collisions and a corresponding
> decline in network throughput and usability on both systems.  Anything
> that involves reading or writing more than 64k or so -- e.g., NFS work,
> web browsing, Fedora updates -- results in collisions, and network
> activity comes to a screeching halt for several seconds.  Removing NFS all
> together and working entirely off of local disk makes no difference.
> (Didn't think it would, but it was worth a try.)

> 
> Both systems had been running RH9 with the exact same hardware, and
> collisions were never a problem.  The laptop dual-boots Windows XP Pro,
> and its network performance is what I'd expect; there's been no observable
> or quantifiable difference in throughput.
> 
> Does anyone have any ideas or suggestions on where I should look?
> Problems with the driver (either) or its configuration?  Or is this one of
> those "Upgrade to FC2 and call us back" situations?
> 
> Thanks!

I would start by verifying the duplex settings on the NIC in the FC1 box
and the port on the switch.  mii-tool should let you check the setting
and force it.  100Mbp connections should be set to full duplex.

I have seen some cisco switches that fight with some systems (in my
experience SUN servers had this problem).  The auto-negotiate would not
work as expected for some reason.  Lock down the speed and duplex
settings on the switch and the NIC to eliminate this as a possible
problem.

-- 
Scot L. Harris
webid at cfl.rr.com

One good suit is worth a thousand resumes.