[CentOS] Disable autoneg on r8169?

Tony Mountifield tony at softins.co.uk
Tue Dec 20 14:34:00 UTC 2011


In article <4EF0939C.9030907 at emmanuelcomputerconsulting.com>,
William Warren <hescominsoon at emmanuelcomputerconsulting.com> wrote:
> On 12/20/2011 12:59 AM, Barry Brimer wrote:
> >> 1. The switch being used has autoneg off and has port set to 100 full duplex.
> >> 2. Many times NIC fails to come up properly during PXE boot:
> >>
> >> Any other ideas?
> > udev rules?
> > mii-tool?

> re-enable autoneg on switch?

Indeed. I once worked at a large ISP where the network admins thought
they were increasing "reliability" by setting all the switch ports to
fixed 100Mb-FD without auto-negotiation. All it achieved was that any
new machines where someone had not remembered to set the fixed config
for the network port would attempt to auto-neg, fail to do so, and fall
back to Half Duplex. That resulted in many collisions and very poor
throughput.

If only they had left all the ports on autoneg and then only set a fixed
mode on specific ports for machines that would not negotiate properly,
which would have been a very small minority! But it's hard to convince
someone whose job function implies that they are the expert...

Sorry for the rant - just pushed a button, that's all!

Cheers
Tony
-- 
Tony Mountifield
Work: tony at softins.co.uk - http://www.softins.co.uk
Play: tony at mountifield.org - http://tony.mountifield.org



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