09-28-2004 06:26 PM - edited 03-02-2019 06:50 PM
In viewing the mac-address table on a 3550 I found 48 static mac address entries like the ones below:
Vlan Mac Address Type Ports
---- ----------- ---- -----
All 000c.316c.6480 STATIC CPU
All 000c.316c.6481 STATIC CPU
All 000c.316c.6482 STATIC CPU
I assume that since they are associated with a port called CPU that it must be some default setup with the 3550.
However, I can't find anything about these static mac address entries documented anywhere on the CCO
Any clues??
09-28-2004 06:38 PM
The one you listed are used by the switch for its Spanning tree bridge MAC addresses for different VLANs. Some will be for STP and other features. here are some
0100.0c00.0000 STATIC CPU - ISL
0100.0ccc.cccc STATIC CPU - CDP/VTP/DTP/PAgP/UDLD
0100.0ccc.cccd STATIC CPU - PVST+
0180.c200.0000 STATIC CPU - STP
0180.c200.0001 STATIC CPU - Pause frames
0180.c200.0002 STATIC CPU - LACP
0180.c200.0003 STATIC CPU - 802.1x
and so on. Here is an example from my lab switch
3550#sh mac-address-table static | inc 000b.4681
All 000b.4681.0000 STATIC CPU
All 000b.4681.0001 STATIC CPU
All 000b.4681.0002 STATIC CPU
All 000b.4681.0003 STATIC CPU
All 000b.4681.0004 STATIC CPU
All 000b.4681.0005 STATIC CPU
All 000b.4681.0006 STATIC CPU
All 000b.4681.0007 STATIC CPU
All 000b.4681.0008 STATIC CPU
All 000b.4681.0009 STATIC CPU
All 000b.4681.000a STATIC CPU
All 000b.4681.000b STATIC CPU
All 000b.4681.000c STATIC CPU
All 000b.4681.000d STATIC CPU
All 000b.4681.000e STATIC CPU
All 000b.4681.000f STATIC CPU
All 000b.4681.0010 STATIC CPU
All 000b.4681.0011 STATIC CPU
All 000b.4681.0012 STATIC CPU
All 000b.4681.0013 STATIC CPU
All 000b.4681.0014 STATIC CPU
All 000b.4681.0015 STATIC CPU
All 000b.4681.0016 STATIC CPU
3550# sh spanning-tree vlan 1
VLAN0001
Spanning tree enabled protocol ieee
Root ID Priority 8192
Address 000f.f8a5.a201
Cost 57
Port 8 (FastEthernet0/8)
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Bridge ID Priority 32769 (priority 32768 sys-id-ext 1)
Address 000b.4681.0000 <<<<--------
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300
Interface Role Sts Cost Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Fa0/8 Root FWD 19 128.8 P2p
3550#
09-28-2004 06:45 PM
Thanks!! I figured they were used for internal purposes (i.e. stp, vlan, etc...), but I just could not find it documented anywhere.
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