netplan does not support can bus interfaces

[Ricardo Delfin]

I've been planning to move my network setup from ifupdown to netplan, but it currently does not seem to support can interfaces, or at least I cannot find any documentation for it. As an example of the kind configuration I have on my /etc/network/interfaces file:

```
allow-hotplug can0
iface can0 can static
    bitrate 500000
    up /sbin/ip link set $IFACE down
    up /sbin/ifconfig $IFACE txqueuelen 20000
    up /sbin/ip link set $IFACE type can bitrate 500000 restart-ms 10
    up /sbin/ip link set $IFACE up
```

[Lukas Märdian (slyon)]

This is not currently supported by Netplan (as of 0.106). Do you know if NetworkManager and/or systemd-networkd already support configuration of CAN interfaces? Could you please link the relevant documentation?

[Ricardo Delfin (rdelfin)]

Thanks for looking into it Lukas. Currently systemd-networkd do indeed support it. I can't find the documentation for how to use it, but I can find the PR that added support: https://github.com/systemd/systemd/pull/9185

I've also set it up using `/etc/network/interfaces` using instructions similar to the following: https://elinux.org/Bringing_CAN_interface_up
Or the following: https://wiki.rdu.im/_pages/Application-Notes/Software/can-bus-in-linux.html

[Justin Cattle (jocado)]

This is something we would also been keen to see supported.

The systemd networkd config required is of this nature:

cat /etc/systemd/network/80-can.network
[Match]
Name=can*

[Link]
RequiredForOnline=no

[CAN]
BitRate=500K
RestartSec=500ms

Cheers,
Just