Often on FreeBSD servers you can see the pfsync0 pseudo-interface up:
[root@bsd ~]# ifconfig
...(skipped)
pfsync0: flags=0<> mtu 2020
syncpeer: 224.0.0.240 maxupd: 128
Unless you are running a pf firewall with redundancy, you won't need this, moreover on CPanel/WHM enabled servers, Cpanel sometimes tries to assign this multicast ip to a domain/customer.
You can safely disable it by adding:
pfsync_enable="NO"
to /etc/rc.conf