Troubleshooting.md

Packet Flow Problems

Problem: I am only seeing a fraction of the packets that I expect to see on the tap interface even though I told openwrt to port mirror all packets to my IP addres.

Solution: You likely have a second interface co-opting your arp assignment in openwrt. Give the mac address of the tap a static arp assignment on the router.

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Problem: Registration is happening for rust process_packet.rs, rust reports that packets are being forwarded through the tun, and ZMQ in ./application reports that the registration is recognized but packets aren't being delivered from tunX to handlePackets.

Solution: Your tun interface is broken, likely the ip rules were set incorrectly. Tear down the tun and re-add the ip rules.

TODO: do this with prereq_onreboot.sh

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Problem: Registrations are happening, and connections are making to through to the application, but we are getting 0 bytes down from the psiphon server.

Solution: make sure that the PROXY header is being added to the traffic.

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Problem: the detector sees registrations and connections, but the application only sees registrations.

Solution: make sure the Tuns are set up correctly, worst case tear them down and run on_reboot.sh again

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Registration Problems

Problem: No registrations are happening, but process_packets is seeing packets from the correct client IPs.

Solution: Generate new keys (see Configuration#generating keys in the wiki)