IP phones register only when voice vlan allowed

[Sai_Prasad_Rao_]

We have 6 floors , we have IP phones connected to switch and PC connects from IP phone. In one floor IP phones register/work only when voice vlan is allowed. If I allow both voice and data on one port then phone not working. In other floors ip phones are working with both voice and data vlans allowed on ports.

[David_Rahn]

yes, we can help more if you tell us more... What kind of phones?

most IP phones need to be told what vlan to tag themselves in to use as voice.

the way you "tell" them is via LLDP / CDP/ DHCP...

if you cant find the difference in the switches look to the dhcp server for option that may be pointing the phones to a vlan...

[Sai_Prasad_Rao_]

no

[Aleixo_Gomes]

is lldp or cdp being used for configuration ?