Interface collisions

David Kelly dkelly at
Mon Mar 31 07:06:53 PST 2003

On Mon, Mar 31, 2003 at 08:20:34AM -0600, Jack L. Stone wrote:
> For the first time within the past few days, I've noticed collisions being
> reported on the public NIC for one of the servers. I'm not sure if it means
> the switch or the NIC is the culprit, so not sure which component may need
> to be replaced.
> Name  Mtu   Network       Address            Ipkts Ierrs    Opkts Oerrs  Coll
> rl1   1500  <Link#2>    00:40:33:5b:bb:5f  6816063     0  7494432     0  66977

Lets see, 67e3 packets had to be retried within their first 64 octets
out of 7.5e6 sent. Actually thats pretty darn good. But ideally if you
are connected  to a full duplex switch it should not happen. "Ideally".
I have no idea how a switch behaves when its caches are momentarily full
but I would guess forcing a "collision" might be a politer means with
faster recovery to back off senders than to simply drop the packet.

Then again a RealTek NIC is the scum at the bottom of the NIC bucket.

David Kelly N4HHE, dkelly at
The human mind ordinarily operates at only ten percent of its
capacity -- the rest is overhead for the operating system.

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