up vote 1 down vote favorite
share [g+] share [fb]

I've set up dead simple NAT: iptables -t nat -A POSTROUTING -s 192.168.1.0/24 -o ppp0 -j MASQUERADE

Everything works almost ok. Almost. The problem I've expirienced is some hosts are not reachable by NAT clients, i.e. there's http://code.jquery.com/jquery-1.4.2.min.js - I can download it from server, but in case of NAT client download stalls on connection stage. I thought its FFs fault, but wget has the same issue. I didn't find any logs/messages that can shed some light on this situtation. Any ideas what's going on? Maybe some tricky thing in sysclt is causing this?

P.S. 3/3 client boxes are expiriencing this issue. This is definitely server trouble.

link|improve this question
25% accept rate
can you post iptables -L -v and iptables -L -v -t nat output? – MrShunz Nov 10 '10 at 11:12
paste.pocoo.org/show/288763 – Daniel Nov 10 '10 at 11:21
What result of executing "telnet code.jquery.com 80 " on problem boxes? Also on linux run before attempt and stop after > tcpdump -vv -i etherwan host code.jquery.com – mmv-ru Nov 10 '10 at 13:48
feedback

3 Answers

up vote 1 down vote

Problem solved: smart switch was dropping packets somewhy. Replaced it and now everything works.

link|improve this answer
which make/model was the device? I think i'm having a similar problem and this would confirm it. Cheers – BoyMars Mar 28 '11 at 7:13
feedback
up vote 0 down vote

Just before your iptables drops any packets, add a -j LOG, running the command again then check /var/log/messages and you'll probably find you're dropping some incoming related packets.

link|improve this answer
there are no DROP rules. none at all. the only rule iptables has is the one i added manually, all other chains and tables got policy=ACCEPT. dmesg and other logs are quiet on this. – Daniel Nov 10 '10 at 11:19
feedback
up vote 0 down vote

Doesn't sound like a NAT problem.

Check the output of ifconfig -a on the client machines. Do you see errors or dropped packets on the interface connected to your LAN?

link|improve this answer
feedback

Your Answer

 
or
required, but never shown
discard

Not the answer you're looking for? Browse other questions tagged or ask your own question.