Openwrt - logging dropped packets outside firewall

Prior experience with Openwrt is beneficial but if you have not, you may at least try setting it up on Virtualbox - [login to view URL] . If you cant even do that, thats fine. I can be your debugging partner :-). I have been working on Openwrt & numerous packages in it. A couple of them modify iptables (heavily) & also modify routing (routes & rules). At some point in time, a few people start to report internet isn't working for them. In essence, their packet is getting dropped (outgoing or incoming). It could be because of iptables or could be because the interface to which Linux kernel is trying to route the packet is down. I am working on iptables logging & need help in logging packets that are dropped NOT because of iptables. I know this is kind of vague but I hope you get the point. Please note - Openwrt devices are too resource constrained so running something like Wireshark etc is possibly not an option unless obviously you can suggest a small enough package which could do this. ------------ To qualify for the project, please answer 2 questions in your proposal. Since I am paying for the domain expertise, answering the questions below will help me guage your skills 1. What is the easiest way dropped packet logging can be done in iptables which will help in catching cases when internal users are having internet issues. Catches - creating a catchall rule is going to be too [login to view URL] no control on table,chains & rule 2. In linux routing - how does route table, rules in it & iptables work together ? The way packet goes through iptables is described at [login to view URL]