I'm reading the netplan documentation and it looks like it does not support multipoint GRE (for NHRP via eg. OpenNHRP).
It's the gap in the documentation or did netplan do not intentionally support multipoint GRE at all and it's not a replacement for ifupdown and legacy /etc/network/interfaces.d/* configs? If so then can netplan and ifupdown be used simultaneously?
I'm trying to port this configuration into the netplan project:
root@2483:~# cat /etc/network/interfaces.d/mpgre0 auto mpgre0 allow-hotplug mpgre0 iface mpgre0 inet static netmask 255.255.255.0 pre-up ip tunnel add $IFACE mode gre key XXX ttl 64 || true up ip link set $IFACE multicast on up opennhrp -d post-down ip tunnel del $IFACE address XXX
Netplan forcing the remote to be defined, which don't make sense for NBMA GRE:
/etc/netplan/10-mpgre.yaml:6:7: Error in network definition: tun0: missing 'remote' property for tunnel mode: gre ^