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Re: Linux shaping packet loss


From: Brielle Bruns <bruns () 2mbit com>
Date: Tue, 08 Dec 2009 09:38:54 -0700

On 12/8/09 8:13 AM, Joe Abley wrote:
I've also heard people say that whatever you think about autoneg in
Fast Ethernet, on Gigabit and 10GE interfaces it's pretty much never
the right idea to turn autoneg off.

From my own experience, turning off auto negotiate can lead to unusual behavior later on that may cause a bit of grief. Our SAN (LHN NSM260) refused flat out to do 802.3ad - giving us duplex errors. Took us around an hour of diagnosing - first we thought it was the switch, then we thought it was the cables we used, etc. Finally it dawned on me that my partner is notorious for hard coding ports on our own equipment.

Low and behold, after her swearing up and down that there's no way its that, we set both ends to auto negotiate and boom, bonding came up happy as a clam.

Only one port on our entire setup that is hard coded - 10BaseT-FD - and thats only because the darn thing refuses to auto negotiate to full duplex for 10BaseT links. I'm almost positive that a year or two down the line, we're going to forget that is there when we change the link to 100BaseT.



--
Brielle Bruns
The Summit Open Source Development Group
http://www.sosdg.org    /     http://www.ahbl.org


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