[CentOS] ethtool

Tue Sep 28 20:25:23 UTC 2010
m.roth at 5-cent.us <m.roth at 5-cent.us>

Stephen Harris wrote:
> On Tue, Sep 28, 2010 at 03:51:17PM -0400, m.roth at 5-cent.us wrote:
>> We've just moved one a new server from our sever room, where I built it,
>> to the datacenter. We want to force autoneg off, and tell it gigabit and
>> full duplex. Using ethtool, I get no errors setting the speed or duplex.
>
> Note that the gigabit over copper standard _requires_ autoneg on.  If you
> do manage to turn it off then you might break things unexpectedly.
>
> http://en.wikipedia.org/wiki/Autonegotiation
>
>    In 1999, the negotiation protocol was significantly extended by
>    IEEE 802.3ab, which specified the protocol for gigabit Ethernet,
>    making autonegotiation mandatory for 1000BASE-T gigabit Ethernet over
>    copper. Specifically Section 28D.5 Extensions required for Clause40
>    (1000BASE-T)
>
Thanks, Stephen, that looks like my answer. That server, and the dhcpd
server, are both fat and happy on gigabit pipes.

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