Server Fault is a question and answer site for system and network administrators. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

So what does the command arp -a do? I've been told it displayed the MAC addresses of all network cards on the computer, but when I ran it, it displayed three MACs for three IPs (, .6, and .8 (24-bit subnet mask)). I assume the first is the router, but what could the other two be?

share|improve this question
up vote 3 down vote accepted

Those would be peer machines in your network that have made contact.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.