For years, I used to configure SIP phone VLAN membership through a DHCP
Here are the details:
– I dedicate a LAN port on a switch to voice VLAN
– somewhere else, I configure a DHCP server to serve LAN addresses within voice VLAN
– any other switch port connected to an other DHCP server is explicitely excluded from voice VLAN
– new SIP hardphones are first connected to the dedicated voice VLAN port:
after several reboots, they get an address within voice VLAN address range and save VLAN tag somewhere within their persistent memory
– SIP phones are then moved to an other switch port: as they boots, they request a LAN address using previously received VLAN tag.
Now I would like to improve this process using LLDP. I ran a couple of tests in my lab and still have some questions:
1. My lab switch sends within LLDP frames, a list of VLANs. One is named
“default” and the other is named “voice”. Do LLDP-capable phones look for a specific name to elect the VLAN tag they will later use to build DHCPDISCOVER request or do they look for something else (medPolicy) ?
2. With LLDP, do you still need your DHCP server to embed VLAN membership data within DHCPOFFER or is it a thing of the past ?
3. Have you been successfull with LLDP on a KVM guest networked to an LLDP-enabled switch through a linux bridge (see ) ?
Where can I find information regarding the line bellow:
echo 16384 > /sys/class/net//bridge/group_fwd_mask