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

[Toke Høiland-Jørgensen]

Ondrej Zajicek <santiago at crfreenet.org> writes:

> On Thu, May 03, 2018 at 03:14:58PM +0200, Toke Høiland-Jørgensen wrote:
>> Ondrej Zajicek <santiago at crfreenet.org> writes:
>> > Ignoring global setting is OK, i just wonder whether some global
>> > EUI-64-based unique ID should not be provided directly by the nest
>> 
>> That might be convenient, yeah. There's the issue of picking the right
>> interface, though; some kind of logic that says "first interface with a
>> configured protocol"? Or should it be a per-protocol type thing?
>
> It would make sense to use an analogous mechanism to 32bit router id,
> just use IPv6-LL address instead of IPv4 address. See 'router id' /
> 'router id from' options and function if_choose_router_id().

Right, that makes sense. A 'v6-ll/64bit router id [from]' config option?
The nest could provide proto_get_router_id64() which would return an
LL-based ID if configured/available and the 32-bit version if it isn't?

> One issue is that if BIRD is started during boot then IPv6-LL
> addresses may not be available immediately after start due to waiting
> for duplicate address detection.

Hmm, true. Should we deal with this (by deferring startup of protocols
that need them, I guess?), or leave it up to administrators to fix their
init scripts? With the fallback option mentioned above it would not be
strictly necessary, we could just fall back to 32-bit... :)

-Toke