07-21-2008 08:37 AM - edited 03-06-2019 12:19 AM
Guys,
I'm having a problem with some servers losing connectivity randomly. Whenever I clear the arp cache, the problem goes away, but eventually resurfaces. I figure this is a layer 2 issue. So I pull the MAC addresses of the servers of interest and take a look at the CAM table. As I look at the MAC addresses one by one, I notice this for one of the particular MAC addresses of interest:
switch1#sh mac-add add 0011.855c.0959
Legend: * - primary entry
age - seconds since last seen
n/a - not available
vlan mac address type learn age ports
------+----------------+--------+-----+----------+--------------------------
Module 12[FE 1]:
* 9 0011.855c.0959 dynamic Yes 5 Gi12/12
Module 12[FE 2]:
* 9 0011.855c.0959 dynamic Yes 60 Gi12/12
Why am I getting two entries for this port, and could this create a problem of any sort? And could anyone explain what 'FE 1' and 'FE 2' is?
Solved! Go to Solution.
07-21-2008 11:07 AM
It looks like you've got a DFC installed on the card in slot 12.
I think this means that the DFC is keeping its own (extra) copy of the L2 forwarding table.
This is normal.
/chris
07-21-2008 11:07 AM
It looks like you've got a DFC installed on the card in slot 12.
I think this means that the DFC is keeping its own (extra) copy of the L2 forwarding table.
This is normal.
/chris
07-21-2008 11:38 PM
Chris is correct. Moreover, there are two forwarding engines that maintain their own CAM entries. That's what you're seeing in the [FE1] and [FE2].
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