I have a satellite uplink and two cellular backups that i terminate via wireguard and handle failover via ospf, the satellite has a cost of 1 and the cellular have a cost of 10 and 11.
Of the two cellular connections, one is slow, unlimited and $20/month (ospf cost 10), the other is fast and billed by the GB (ospf cost 11)
PBR is a new challange for me and im not sure if it will achieve what i need:
When the satellite link is up, i want all traffic to use it and when its down i want to direct high priority traffic over the expensive cellular if its up and then over the slow cellular as a last resort. All other traffic should use the slow cellular and never the expensive link.
Im assuming a starting point would be to set the cellular links to have the same cost, and maybe add an output rule to drop low priority traffic on the expensive link. But im coming up empty when i try to set PBR rules to pin the appropriate traffic to the desired uplink, and setting the cost the same defeats my goal of having the slow cellular as a last resort for priority traffic.