Linux

If you use tacppd bundle, you must enable multicast on your Linux box. Exellent documentation available at Multicast-HOWTO (http://www.linux.org/docs/ldp/howto/Multicast-HOWTO.html). In several words:

Check

if it is enabled, and if not, enable Multicasting in the kernel

Configure

multicast routing with command:

/sbin/route add -net 224.0.0.0 netmask 240.0.0.0 dev eth0

See,

if Linux box connected to multicast group, see /proc/net/igmp file. You will see something like:

Idx Device : Count Querier Group Users Timer Reporter 

1 lo : 0 V2 010000E0 1 0:ED688817 0 

2 eth0 : 2 V2 010101EF 1 0:FFFFED3F 1 

              010000E0 1 0:ED688817 0

(if you stop tacppd, than you do not see string where Reporter=1).