I have been trying to track down an Email problem between two locations,
and I have found what I believe to be a problem with MTU/fragmented packets.
I have had my tunnel up and working for quite a while. Things were
perfect! Suddenly, it seems like it is not fragmenting packets over the
tunnel any more. I am not sure if it is a change that I made and forgot
about - or what could have caused it.
If I use the commend "ping 192.168.2.254 -s 1472" to ping across the
tunnel, it works fine. "ping 192.168.2.254 -s 1473" or larger does not.
I have the "allow fragmented packets over ipsec" checked in the advanced
tab on both m0n0walls.
Any other ideas?