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no MAC address on switch port

Wassim Aouadi
Level 4
Level 4

Hi,

There 's a Cisco IP phone that sits between a PC and the switch port. On the switch port, no MAC address is learned. However, the switch is able to detect the IP phone and deliver power to it:

TNSWACCS04A1#sh power inline fa1/0/13

Interface Admin  Oper       Power   Device              Class Max

                            (Watts)                           

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

Fa1/0/13  auto   on         5.0     IP Phone 7911       2     15.4

Interface  AdminPowerMax   AdminConsumption   

             (Watts)           (Watts)          

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

Fa1/0/13              15.4                 15.4

TNSWACCS04A1#

TNSWACCS04A1#

TNSWACCS04A1#sh mac add dyn int fa1/0/13

          Mac Address Table

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

Vlan    Mac Address       Type        Ports

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

TNSWACCS04A1#

any idea?

Switch is Catalyst 3750 with IOS version  12.2(58)SE1

Wass

1 Reply 1

Wassim Aouadi
Level 4
Level 4

I found it.

The command I was typing is "show mac address-table dynamic interface...". However, in this situation, MAC addresses are statically learned via port-sec sticky feature:

TNSWACCS04A1#sh mac add dynamic int fa1/0/13

Mac Address Table

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

Vlan Mac Address Type Ports

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

TNSWACCS04A1#

TNSWACCS04A1#sh mac add

TNSWACCS04A1#sh mac add static int fa1/0/13

Mac Address Table

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

Vlan Mac Address Type Ports

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

20 7071.bc5e.0672 STATIC Fa1/0/13

2222 108c.cfe0.98af STATIC Fa1/0/13

Total Mac Addresses for this criterion: 2

TNSWACCS04A1#

issue solved.

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