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Hi! I have a lot of problems with m0n0wall regarding packet fragmentation. About 6 months ago I setup some lan-to-lan ipsec links via m0n0 boxes at each location then using verson 1.2b<n>. Almost all locations are connected to the internet via PPPOE links. At first all seemd OK and working but when I tried to "extend" the MS AD domain over those ipsec links the errors popped out. After some debugging I discovered the problem was m0n0 silently dropping "oversized" packets. The packets are really not oversized but are greater than the effective MTU on the pppoe link of 1492 bytes. I searched the web, mailing lists etc but found nothing special. I tried with special firewall rules with "allow fragmented packet" etc with no success. I went back to version 1.1 which was considered stable at the time and the things started to work (with allow fragmets firewall rules). I impatiently waited for the new m0n0 version and finally installed it but... again with same problems. Somehow, I managed to partially fix this problem (using firewall rules, reduced mtu etc). Right now, the traffic is flowing if it is initiated from the site which has "normal" ethernet connectivity to the internet (mtu 1500 bytes). If initiating some ping with packets grater than 1500 bytes all is working as expected. BUT if I try to ping from the remote site, which has pppoe connection and a mtu of 1492 bytes, the packets are getting dropped silently... Does anybody have any hint / idea / comment on this "fragmentation" problem with m0n0? I'm not very familiar with *BSD platforms (I'm more a Linux fan...) but are there any specifics about packet fragmentation in *BSD kernels? Maybe some "default security feature" I'm not aware of? Kind regards, Mauricio |