dhcpd synchronization

Hi,

I would like to use the synchronization between two dhcpd to sync the 
leases.

Host 192.168.128.3: start dhcpd with -y 192.168.128.3 -Y 192.168.128.4

Host 192.168.128.4: start dhcpd with -y 192.168.128.4 -Y 192.168.128.3

=> with tcpdump I can see udp-Traffic between the hosts via port 8067 
even without a matching pf rule?

1) How do I handle the sync traffic correctly with pf? Should I prefer 
"-y IFNAME -Y IFNAME" ?

2) How do I verify correct lease sync?

When I "tail /var/db/dhcpd.leases" on both hosts, most entries on one 
side are reflected on the other, but not all?


kind regards

Thomas