show mac-address command gives different results

[cpama]

Hi there.

I'm noticing that when I run the show mac-address command it gives me differnet results.

I'll run it and get 30 results in my list.  Then I'll run it again a few minutes later and it seems like I have more items.

I'm not a networking person so if this is a basic question, I apologize in advance.

Thanks.

[paulgear]

Hi cpama,

That is normal behaviour whenever you have a relatively dynamic network.  The 'show mac-address' command shows you what the switch has learned about the environment, based on which nodes are talking at the time.  As new nodes talk they are added to the table.  If a node doesn't talk for a certain period of time (see the "MAC Age Time (sec)" entry in the output of 'show system-information'), then it is removed from the table.  You can control the timer by using the 'mac-age-time' command, although the default seems to work pretty well for me.