[CentOS] disable auto-negotiation gigabit ethernet

Tue Mar 20 17:19:20 UTC 2012
m.roth at 5-cent.us <m.roth at 5-cent.us>

sebastian wrote:
> Am 20.03.2012 16:33, schrieb m.roth at 5-cent.us:
>> Michael Simpson wrote:
>>> On 20 March 2012 14:29, sebastian<centos at secretusenet.com>  wrote:
>>>> I can not disable the auto-negotiation (eth1) on my centos 6.2 via
>>>> ethtool or /etc/sysconfig/network-scripts/ifcfg-eth1
>>> Autonegotiation is mandatory for 1000BASE-T as both sides have to work
>>> out which pairs they are going to use.
>>> Check:
>>> 1)cable
>>> 2)switchport
>>> if those are ok then you probably have a driver/NIC problem
>> Two more things:
>>     a) make sure the router/switch isn't pegged or being changed to
>> slower
>>     b) are your cables ok for gigabit. I know this sounds absurd, but I,
>>          personally, have changed cables, and it made the difference

> Thanks, but is a remote-server, the server is in another datacenter. I
> can not change or check the cables/switch - and the stuff in the
> datacenter is not very usefull. I'm hoping to solve the problem with
> disable the auto-negotiation.

Hey - I was assuming it wasn't under your control, any more than mine,
here at work, are under mine. When I have this problem, I file a ticket,
and eventually get to talk to the admins who *do* have control over that.
And yes, too many times, I get a "oh, it is pegged, I have no idea how
that happened...." from them before they fix it.