"Austad, Jay" <austad at marketwatch.com> writes:

> You shouldn't see any collisions at all on your network interface, I just
> checked 7 or 8 different boxes of mine, some have been up for 6 months or
> more serving Real Video content out at around 5-10 Mb/sec during the day,
> and I don't show any collisions at all on them.
> 
> Chances are that your duplex is mismatched.  Maybe a cheap NIC could do it
> too..  probably doesn't hurt anything if you only have .1% though.
> 

Running a real 3c59x, I show:

gw:Mail# w
  5:47pm  up 15 days,  1:25,  5 users,  load average: 2.39, 2.16, 2.11

gw:Mail# ifconfig
eth0      Link encap:Ethernet  HWaddr 00:A0:24:D1:4F:3A  
          inet addr:63.224.10.74  Bcast:63.224.10.79  Mask:255.255.255.248
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:12906269 errors:5 dropped:0 overruns:0 frame:5
          TX packets:14615922 errors:0 dropped:0 overruns:0 carrier:431
          collisions:39926 txqueuelen:100 
          Interrupt:10 Base address:0x9400 

So, small percentage of collisions, but definitely non-zero.

This system is going into the 100 megabit portion of a 10/100 "hub
with switch" (amazingly weird intermediate hardware generation; it has
a 10mb collision domain and a 100mb collision domain with a switch
connecting them) which is connected to a real 10/100 switch which is
finally connected to a Cisco 675 DSL router (most of the traffic on
this system is external).
-- 
David Dyer-Bennet      /      Welcome to the future!      /      dd-b at dd-b.net
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