For security reasons, I upgraded to 2.4.23 last night. Now, suddenly, IP
masquerading seems to be broken. When I use SNAT instead of
masquerading, everything works.
Unfortunately, I think it's hard to reproduce the problem. Right after
booting .23 for the first time, everything seemed to be okay. The
problems started just an hour ago, after having the server running for
fifteen hours without any problems.
Unfortunately there's not much more information I can provide. I can
attach my iptables/rule/route file and keep my machine running in case
anyone needs/wants more information. For now I'll just stick with SNAT.
It works good enough for me.