Comment by imoverclocked
2 days ago
> R1 & R2 are IPv6 only with no IPv4 anywhere on their interfaces (but carry IPv4 routes in their table)
… proceeds to traceroute with IPv4 addresses showing up for each router…
It’s neat but still requires IPv4 to be configured on the router? What am I missing?
You still need at least one IPv4 address somewhere if you want to send ICMP back, yes. (Typically a loopback, i.e., something not connected to a specific interface. Routers use loopback interfaces for rather different purposes than a Linux workstation.) But you don't need to set up an IPv4 address on every interface, so you don't need a linknet plan.
You can also forego the IPv4 addresses entirely, but then traceroute (and presumably also stuff like Path MTU Discovery; have consistent MTUs!) won't work. traceroute is often broken for entirely different reasons, though.