How to add custom route to all k3s nodes?

[ralimardanov]

Hello.
First of all, I want to thank you for such nice module! It helped us a lot.

I have a question, so we have configured infra with your module and made site-to-site vpn with other client.
To reach clients network, traffic should go through VPN.
For containers running inside cluster, we have to add 1 route in Hetzner network, but because it's external subnet, it asks us to manually add route on all nodes:

When adding manually route to one of our nodes, connection works. The thing is we wanted to have this automatically, especially for autoscaling nodes. I tried to search a bit about how servers are created and if there is any way to pass such configuration, but with no luck.
@mysticaltech or anyone else who has faced such situation, what can you suggest?
Thanks in advance!

PS: I don't know if kube.tf file is needed for this case, so I didn't add it right now.

[mysticaltech]

@ralimardanov That's certainly possible, but we do not explicitely have that feature that this moment. It would need to be added, For instance you could add a variable with an array of routes to add to each node, this would be done in the internal host module (see module/host) most probably, as it's the part in common to all nodes.

@M4t7e FYI, maybe you'd have some ideas for that too.

[ralimardanov]

Hello @mysticaltech , thanks for your fast reply.
I tried to add something like this in cloudinit.yaml.tpl in module/host templates:

network:
version: 1
config:
- type: physical
name: eth1
subnets:
- type: static
address: <destination_subnet>
gateway: <gateway_address>

But it didn't seem to work out. Do you have anything on mind about how it should be done?

[mysticaltech]

@ralimardanov We already add a route somewhere, just search for that and do the same thing.