Hi i'm trying to find out what i've said on topic. I've taken a look at this mail: http://lists.netfilter.org/pipermail/netfilter/2000-August/004878.html So i think that if you pass a packet to POSTROUTING taht exceeds MTU, netfilter will try to send it anyway right? Because you have to fragment before, 'cos netfilter doesn't expect a packet exceeding MTU right? But that fragmentation how could be done? I've seen in the above mail some C-code building a fragmentation module for doing this, but it's not included in the official kernel tree? Another question: in this mail i've not understood if fragmentation is done by such module or by a /proc entry; the mail it's quite old, so what's the situation actually? thanks for any RTFM or help :) Regards -- Debian Powered GNU/Linux User #373118 Bedogni Luca - Blog | http://blog.lucabedogni.it Site | http://www.lucabedogni.it Debianizzati - www.debianizzati.org | Founder Member -- Token Ring, n.: a local area network architecture, perhaps a future replacement for SNA. Not to be confused with the Tolkien Ring, although the purposes are similar: "One Ring to rule them all, one ring to find them, one ring to bring them all and in the darkness bind them, in a LAN with more nodes where the stations lie."