[Sheflug] Rooting out "routed" & getting out of a "bind"

[James Wallbank <nospam [at] lowtech.org>]

Hello All,

When I got IP masquerading working on my home network I was feeling 
pretty smug. I could surf the net from any of my machines. Admittedly 
I didn't understand _exactly_ what I'd done, but hey, it worked! And 
that was good enough for me. Or it should have been. But no, I just 
had to fiddle around...

It worked!
==========

Thanks to Alex, José and other's advice, I sorted out the default 
route on my Debian 2.2 (r2) gateway by adding a one-liner to 
/etc/ppp/ip-up/ that added the default route to the routing table as 
soon as the link went up:

route add default gw "$PPP_REMOTE"

Then to get IP masquerading up I added a little script to /etc/init.d/

echo > 1 /proc/sys/net/ipv4/ip_forward
ipchains -P forward DENY
ipchains -A forward -i ppp0 -j MASQ

Temptation
==========

Okay, so I was happy... Oh, those joyous days... I could connect from 
any of the machines on my home network. What joy, what innocence! But 
then the serpent of techno-fiddling tempted me, and I have to 
confess, I succumbed. "Why don't you try messing around with BIND?" 
it said. "And while you're using dselect, why don't you try 
installing "routed" and see what happens?".

Cast out of Routing Eden
========================

Well I'll tell you what happened. The whole thing stopped working. So 
I rummaged around in /etc/init.d/ and /etc/ppp/ip-up/ trying to get 
rid of anything that might be running "bind" or "routed" and checked 
things like "resolv.conf" and "hosts" to see if anything had been 
written there that I didn't want. I rebooted and checked with ps ax - 
I'd successfully got rid of bind and routed. I checked to see that my 
routing table was still the same as when it worked (it was).

* Now once I've connected via ppp0 ifconfig reports 3 perfectly good 
networks, lo, eth0 and ppp0.
* When I type netstat -rn I get exactly the same routing information 
as I got before, when it worked.
* When I try to access the net from my gateway machine I can.
* But when I try to access the net from another machine on the LAN, nothing!

Please help!
============

Any suggestions? What can installing "bind" or "routed" have changed 
so that I can't get through my gateway? As far as I can see 
everything is just the way it was... but clearly something has 
changed. Can you suggest other files I should check, please?

Cheers,

James
=====
-- 
who: James Wallbank
org: Redundant Technology Initiative
tel: +44 114 2495522
fax: +44 114 2495533
eml: rti [at] lowtech.org
web: www.lowtech.org
loc: Access Space
      1 Sidney Street
      Sheffield
      S1 4RG
      UK
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