[Babel-users] Specify router-id explicitly

[Juliusz Chroboczek]

>> There's no equivalent config file option, since I'm a little worried about
>> config files being copied between nodes.

> This departs from the previous mantra "All command-line options are also
> available as a configuration statement".
> 
> This is an issue for OpenWRT, because we simply translate OpenWRT-style
> options into their equivalent babeld-style config options (basically,
> "s/_/-/g").

That's the whole point -- this option is dangerous, and should not be
available in the OpenWRT config file.  This will hopefully prevent people
from flashing routers that all have the same router-id.

Please do not make this option available in the OpenWRT config file.

-- Juliusz