Unix How-To: Checking on Collisions [Video]

dmfe1 1500 default 0.0.0.0 0 0 0 0 0 0

This is a Sun system with two network interfaces, only of which is un use (dnfe0) and, of course, the loopback (lo0).

The number of collisions tells us how many packets (ethernet frames) ended up colliding (being put on the network medium at the same time as) other packets, the result being that each of them would have to be recalled and resent by their respective network interfaces shortly afterwards. A high collision rate would indicate that the network is very busy, possibly overloaded. The more collisions you have, the more packets have to be resent, the more traffic you have and so on.

You can try using the expr command to calculate the percent of collisions, but you aren’t likely to get an answer that’s worth much:

boson$ expr 27690 / 1738653700

You can append a bunch of zeroes to your collision count, but …