Add initial support for EXOS

[sdargoeuves]

No description provided.

[sdargoeuves]

I haven't looked at the other part of the docs yet (supported platform...), and I also will add in a near future, ospf, maybe vlan... not sure what else yet.

[ipspace]

Great job, almost picture-perfect ;) Just had to fix a symlink that I probably borked a long time ago, and added a few missing entries in "libvirt" documentation.

However, the MTU configuration fails, and it looks like packet forwarding doesn't work, and IPv6 RAs are not sent:

04-mtu:

• Test topology
• Test results

07-router:

• Test topology
• Test results

I could merge this PR as-is and then you could fix these minor details in a fresh PR to keep things simple. Just tell me how you'd like to proceed.

[ipspace]

FWIW, I found the MTU issue -- EXOS cannot set the IP MTU below 1500. You have to set the MTU range in device features. This is what we have on SR Linux.

features:
  initial:
    min_mtu: 1436
    max_mtu: 9500

EXOS seems to have min_mtu at 1500 and max_mtu at 9216

[sdargoeuves]

Great job, almost picture-perfect ;)

🥳 thank you!

For the other issues, I'll look into this existing PR.
I was looking at the OSPF, and vlan modules... but maybe I need to slow down and get the initial correctly working first!! But whilst looking at the OSPF, I did see a forwarding issue... fixed with the commands: enable ipforwarding vlan xxx and enable ipforwarding ipv6 vlan xxx

I'll try to sort this later today, or tomorrow.

[ipspace]

@sdargoeuves -- do you want to fix IP forwarding as well or should I merge it?

[sdargoeuves]

Please do not merge, I will create a new branch& PR, where I've got your changes, and more fixes and features.
I got into a git fight last night, which i think is now won!
I'm running a few more tests this morning, and should push soon