[FROG] how to make FRR know about configured netns on a centos system?

[David Lamparter]

Hi Roman,


depending on what you want to do, there are 2 different approaches to
network namespaces with FRR:

(a) using them to implement VRFs and have FRR be aware of them
(b) using them to implement virtual routers and run FRR inside of them

For a management interface separation -- where you don't need any
interaction between the management and routing netns -- I would suggest
you do (b).

Now, unfortunately the standard init scripts won't start FRR in a
network namespace for you.  You'll have to wire that up for yourself.
But on the other hand, after that's done you just have a "normal" FRR
installation and don't need to deal with VRFs.  If you want to run more
than one FRR "virtual router", you can use the `-N` option.  In that
case each netns runs the full set of all daemons.

If you want to do (a), there is the `--vrfwnetns` option to pass to
zebra at startup, but I don't actually know the details on this since I
haven't run such a setup.
[https://frrouting.readthedocs.io/en/latest/zebra.html#cmdoption-zebra-n]

Lastly, if you want to use Linux kernel VRF support, that works by
creating "vrf" type devices inside the 1 network namespace.

Cheers,


-David