Now this is strange.
I am running Debian 9 on kernel Linux 4.9.0-8-686-pae
I am moving from iptables to nftables on my second VPS (also running the same Debian etc) Last night I was testing various aspects of the firewall and tried IPV6 pings etc between the 2 VPS. I kept getting network unavailable for the one with iptables still. It is on Hobgoblin. IPV4 all OK. No IPV6 connection.
A check showed it was only using the fe80 link-local address.
I have checked the interfaces file and it is the same as the one on my other VPS (except for the actual addresses of course.) Done a shutdown/boot through Xen. Nothing
Is netplan a thing on Debian 9, though I don't see any signs of it being there.
Right at the beginning I checked thing like firewalls etc.
Keith