Cisco Phone

[nettam.naveen]

Hi,

This is regarding to Vioce VLAN Mac address detection,

In my organization we are using cisco 3560 46 port access switch and each port is connected with cisco ip telephone and some pc are connected with cisco ip telephone for Data usage.

 In every switch i configured data vlan for PC and voice vlan for ip telephone for reference sample configuration is mentioning in below,

#switchport mode access

#Switchport access vlan***

#switchport voice vlan***

#spanningtree portfast

this is configuration which we configured in access switch, know i have qution about mac address learning Cisco IP phone mac address is detecting two times in each port like

#show mac address table | incluse ****

104    0026.0bd8.3aea    DYNAMIC     Gi1/0/1
203    0026.0bd8.3aea    DYNAMIC     Gi1/0/1

104    0026.0bd8.3aea    DYNAMIC     Gi1/0/1

Know my query is why the mac address is showing two times in show commends.

Thank you.

[marco.merlo · Accepted solution]

Hi,

on  the platform you are dealing with it seems the expected behaviour

https://tools.cisco.com/bugsearch/bug/CSCea80105

I noticed the same issue some years  and indeed it didn't affect user traffic.

Cisco IP phones send CDP packets both on voice and data vlan. Some platforms do not populate dynamic mac address table  while getting cdp packet on data vlan when voice vlan is configured some others do.

Regards

M