Did something change in the kernel between 2.4.17 and 18 concerning ICMP
fragmentation?  I've been noticing (and getting complaints from local
users) that some web sites are unaccessable.  Sounds like the problem of
some ISP's / routers not allowing ICMP fragmentation packets.  I checked
some of my firewalls and the problem appears to show up on kernels
2.4.18 and higher.

Anyway, the work around according to kernel documentation is to add this
line to the iptables rule set:

iptables -A FORWARD -p tcp --tcp-flags SYN,RST SYN \
-j TCPMSS --clamp-mss-to-pmtu

This does appear to work for clients behind the firewall going to the
Net.  However, this does not fix the problem for the fw box itself.

Anyone else run into this and find a fix?

-- 
John Hawley
BGEA / Info Tech Svcs
612.335.1334
jhawley at bgea.org