With T987 beeing already complete for L2TP we should use the same for PPTP.
Proposal, change CLI from:
vyos@vyos# show vpn pptp remote-access { authentication { mode radius radius-server 172.16.100.10 { key barbarbar } radius-server 172.16.100.20 { key foofoofoo } }
I'd rather prefer:
vyos@vyos# show vpn l2tp remote-access { authentication { mode radius radius { server 172.16.100.10 { key barbarbar } server 172.16.100.20 { key foofoofoo } } }
In other words, remove top level tag nodes from radius-server and introduce a regular RADIUS node, thus we can add additional features, too.