Diyaa, this is about the *outside* tunnel IP address that wireguard uses to establish connection, not about inside routing. BR, Nico Diyaa Alkanakre writes: > The better approach would be to exclude the IPs from your WireGuard AllowedIPs. I always exclude IPs if I can before doing policy based routing. > > https://www.procustodibus.com/blog/2021/03/wireguard-allowedips-calculator/ > > > Jun 21, 2024, 5:15 AM by nico.schottelius@ungleich.ch: > >> >> Hello again, >> >> I'm sorry to flood the mailing list with wireguard bugs, but it seems >> there is yet another routing bug in wireguard - happy to be wrong, but >> here are my findings: >> >> a) system has source based routing on via ip rule: >> >> [11:07] server141.place10:~# ip rule ls >> 0: from all lookup local >> 32765: from 192.168.1.0/24 lookup 42 >> 32766: from all lookup main >> 32767: from all lookup default >> [11:07] server141.place10:~# ip route sh table 42 >> 194.5.220.0/24 via 192.168.1.254 dev eth1 proto bird metric 32 >> 194.187.90.23 via 192.168.1.254 dev eth1 proto bird metric 32 >> 212.103.65.231 via 192.168.1.254 dev eth1 proto bird metric 32 >> [11:08] server141.place10:~# >> >> This should ensure that packets towards 194.187.90.23 travel via eth1. >> >> b) tcpdump for verification >> >> Using "tcpdump -ni any port 4000" I observe: >> >> 11:10:22.445638 eth0 Out IP 192.168.1.149.58591 > 194.187.90.23.4000: UDP, length 148 >> 11:10:27.447026 eth0 Out IP 192.168.1.149.58591 > 194.187.90.23.4000: UDP, length 148 >> 11:10:32.448329 eth0 Out IP 192.168.1.149.58591 > 194.187.90.23.4000: UDP, length 148 >> 11:10:37.449719 eth0 Out IP 192.168.1.149.58591 > 194.187.90.23.4000: UDP, length 148 >> >> c) Route in main table >> >> There is indeed a route in the main routing table that matches, too: >> >> [11:08] server141.place10:~# ip r get 194.187.90.23 >> 194.187.90.23 via 10.5.2.123 dev eth0 src 192.168.1.149 uid 0 >> cache >> >> d) ip rule not working (?) >> >> So from what I can observe it is that ip rule does not work together >> with wireguard / wireguard routing takes the route from main fib instead >> of from the separate table. >> >> I am not sure if this is related at all to the IP address binding bug, >> but it appears in a similar context from our tests. >> >> BR, >> >> Nico >> >> -- >> Sustainable and modern Infrastructures by ungleich.ch >>