show mac self

[visacemea]

On 3550 and 2950s - does anymore have info on these sequentially numbered mac addresses? Web searches yield little.

cisco>sh mac self

Non-static Address Table:

Destination Address Address Type

------------------- ------------

0006.d7d0.3280 Self 1 VLAN1

0006.d7d0.3280 Self 4 VLAN1

0006.d7d0.3281 Self 1 VLAN1

0006.d7d0.3282 Self 1 VLAN1

0006.d7d0.3283 Self 1 VLAN1

0006.d7d0.3284 Self 1 VLAN1

0006.d7d0.3285 Self 1 VLAN1

0006.d7d0.3286 Self 1 VLAN1

0006.d7d0.3287 Self 1 VLAN1

0006.d7d0.3288 Self 1 VLAN1

0006.d7d0.3289 Self 1 VLAN1

0006.d7d0.328a Self 1 VLAN1

0006.d7d0.328b Self 1 VLAN1

0006.d7d0.328c Self 1 VLAN1

0006.d7d0.328d Self 1 VLAN1

0006.d7d0.328e Self 1 VLAN1

0006.d7d0.328f Self 1 VLAN1

--More--

Thanks in advance

[Giuseppe Larosa]

Hello David,

a switch needs a unique MAC address for each L2 port on it to be used as source MAC address for STP messages and for other L2 protocols like CDP and DTP.

you can see the block of MAC addresses in modular switches with sh module the show you used is helpful on fixed config switches.

Example:

sh module

Mod Ports Card Type Model Serial No.

--- ----- -------------------------------------- ------------------ -----------

1 24 CEF720 24 port 1000mb SFP WS-X6724-SFP SAL1131WBE1

2 16 16 port 1000mb GBIC ethernet WS-X6416-GBIC SAL06251KFT

3 8 CEF720 8 port 10GE with DFC WS-X6708-10GE SAL1231ZCER

4 8 CEF720 8 port 10GE with DFC WS-X6708-10GE SAL1231ZCEU

5 2 Supervisor Engine 720 (Active) WS-SUP720-3B SAL1132WU89

9 48 CEF720 48 port 10/100/1000mb Ethernet WS-X6748-GE-TX SAL1131WHRF

Mod MAC addresses Hw Fw Sw Status

--- ---------------------------------- ------ ------------ ------------ -------

1 001c.58be.ac90 to 001c.58be.aca7 2.6 12.2(14r)S5 12.2(18)SXF1 Ok

2 000a.4124.bd00 to 000a.4124.bd0f 2.2 5.4(2) 8.5(0.46)RFW Ok

3 001e.f7f8.5930 to 001e.f7f8.5937 1.4 12.2(18r)S1 12.2(18)SXF1 Ok

4 001e.f7f8.5a58 to 001e.f7f8.5a5f 1.4 12.2(18r)S1 12.2(18)SXF1 Ok

5 0016.4708.5388 to 0016.4708.538b 5.4 8.4(2) 12.2(18)SXF1 Ok

9 001c.58e2.92e0 to 001c.58e2.930f 2.6 12.2(14r)S5 12.2(18)SXF1 Ok

Hope to help

Giuseppe