sometimes the lock file isn't handled correctly and lldp won't start.
[root@localhost src]# ./lldpd -d A -f
/var/run/lldpd.sock:19
[Error] Unable to bind to the unix domain socket for client registration!
[Error] Unable to listen to the unix domain socket for client registration!
[INT] eth0 (index 2) found. Initializing...
[INT] 'eth0' is index 2
[INT] eth0 MAC: 00 0c 29 01 c7 72