Point to point network configuration

[eshikhov]

Does talos support network setup in pointopoint mode?

Configuration example
etc/network/interfaces

auto eth0
iface eth0 inet static
   address (ADDITIONAL IP)/32
   pointopoint (MIAN IP)
   gateway (MIAN IP)

netplan

network:
  ethernets:
    ens3:
      addresses:
      - (ADDITIONAL IP)/32
      routes:
      - to: 0.0.0.0/0
        via: (MIAN IP)
        on-link: true
      nameservers:
        addresses:
        - 8.8.8.8
        search: []
  version: 2

[smira]

I'm not sure what kind of a route is created from this config. It might not be exposed in the machine config.

[vladimirfx]

Example for the guest:

$ ip address show

ens18: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether <mac> brd ff:ff:ff:ff:ff:ff
    altname enp0s18
    inet <guest_ip>/32 scope global ens18
       valid_lft forever preferred_lft forever

$ ip route show

default via <host_ip> dev ens18 proto static onlink 
<guest_ip> via <host_ip> dev ens18 proto static onlink

[smira]

I think I need to dig more to understand what default via <host_ip> dev ens18 proto static onlink means

Simple <host_ip> onlink which means it's directly routeable without a gateway is available by specifying a route on a link without a gateway.

[vladimirfx]

Yes <host_ip> is available on the link (it is main IP on bridge device on the host OS). So host IP is added as directly available on the link and set as the default gateway.

[smira]

So I guess I don't quite understand why it needs default via <host_ip> given it's point-to-point

[vladimirfx]

Host is gateway for its guests. Hetzner call this “routed mode” networking for virtualization.