network/routing wonkiness

[David A. Bandel]

On Mon, Jul 23, 2012 at 11:10 AM, Lonni J Friedman <netllama at gmail.com> wrote:
[snip]
>>
>> short answer:  firewall (iptables) rules.
>>
>> long answer:
>> iptables -t nat -i $EXTERNAL_INTERFACE -p tcp --dport 80 -j DNAT $INTERNAL_IP
>>
>> If you understand the above, you'll understand what's happening.  You
>> must hit the external IP by entering via your router's external
>> address from outside.  You can't hit your external address from inside
>> because the packets aren't entering via the external interface, but
>> via the router's localhost interface.
>>
>> So basically, it's a packet routing issue inside your router.  If you
>> can get in via a CLI and remove the $EXTENAL_INTERFACE (basically
>> allowing the packet to port 80 to come from anywhere, then it should
>> start working (but may break other things).
>
> Thanks, that makes sense.  Unfortunately, while my router does have
> shell access, it uses ipchains (rather than iptables), with a 2.0.x
> kernel.   I never could grok ipchains rules, no matter how hard I
> tried.  There are tons of ipchains -> iptables conversion tools, but
> sadly, not the reverse.  Anyway remember how to do this with ipchains?
>

You're joking.  If this thing is running Linux now, you should be able
to upgrade to OpenWRT (https://openwrt.org/).  I would recommend it.
Then, maybe someone can help (although I doubt you'll need it).
ipchains is ancient and (AFAIK) unsupported.  not even stateful.

Ciao,

David-
-- 
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