[PATCH 3/3] babel: Add option to randomise router ID

[Toke Høiland-Jørgensen]

Toke Høiland-Jørgensen <toke at toke.dk> writes:

> When a Babel node restarts, it loses its sequence number, which can cause
> its routes to be rejected by peers until the state is cleared out by other
> nodes in the network (which can take on the order of minutes).
>
> There are two ways to fix this: Having stable storage to keep the sequence
> number across restarts, or picking a different router ID each time.
>
> This implements the latter, by introducing a new option that will cause
> Bird to pick a random router ID every time it starts up. This avoids the
> problem at the cost of not having stable router IDs in the network.

BTW, I would also like to implement the EUI-64-based router ID
assignment that babeld does, since it can significantly improve protocol
efficiency in some v6 deployments. But that would require ignoring the
global setting for router ID; is that acceptable, if it's made a
configuration option?

-Toke