Re: ftp over RH router

> On Thu, Mar 13, 2003 at 06:33:25PM -0500, Keith Mastin wrote:
>> To clarify things...
>>  you have 2 subnets A and B inside the firewall
>>  there is no ftp server on the firewall
>>  all traffic between subs A and B goes through the firewall
>>  the ftp server is on sub B
>>  you can ftp from a windows box on sub A to the world
>>  you cannot ftp from same windows box on sub A to sub B
>>  you cannot ftp from world to sub B
>> ... is this correct? If not, please set me straight.
>
> OK sorry, I should have discribed that a bit better.
>
> I have one subnet behind a linux firewall with windows boxes
> I am ftp-ing to the world:
>
> The linux box has a cable connection to the internet (Net A)
> and I also have another box at a different location with a DSL
> connection to the internet wich has a ftp server (Net B)
>
> I am trying to ftp to Net B from Net A. I have tryed it with a
> standallone windows box connected to the internet and it works, thus
> there should be nothing wrong on the Net B side and there must be
> something wrong with the masquerading/forwarding if I have the Net A
> firewall basically as
> complete passthrough.
>
> I don't get it. I have the same arangement on Net B but all the windows
> boxes can ftp out perfectly. (Same distro RH72)

Okay, for iptables, there's a few things to do... There's a good little
script located here that will show you the way through most of it.
http://lists.netfilter.org/pipermail/netfilter/1999-November/002793.html

Pay particular attention to the modules used. ip_conntrack_ftp is the
important one. If that's not inserted, nothing will work for forwarding
ftp in iptables.

HTH


-- 
Keith Mastin
BeechTree Information Technology Services Inc.
Toronto, Canada
(416)696 6070