Server-ipv6 is incompatible with 'nopool' option

OpenVPN won’t start due to the following error:

Options error: --server-ipv6 is incompatible with ‘nopool’ option

I have a very basic server configuration as follows:

openvpn vtun1 {
mode server
persistent-tunnel
replace-default-route {
}
server {
name-server 1.1.1.1
name-server 8.8.8.8
subnet 172.18.19.0/24
subnet fc00::/64
}
tls {
ca-cert-file /config/auth/openvpn/ca.crt
cert-file /config/auth/openvpn/server.crt
dh-file /config/auth/openvpn/dh2048.pem
key-file /config/auth/openvpn/server.key
}
}

This is in /var/run/openvpn/vtun1.conf where the problem appears to be server 172.18.19.0 255.255.255.0 nopool:

verb 3
user openvpn
group openvpn
dev-type tun
dev vtun1
persist-key
iproute /usr/libexec/vyos/system/unpriv-ip
proto udp
multihome
persist-tun
push "redirect-gateway def1"
mode server
tls-server
topology net30
server 172.18.19.0 255.255.255.0 nopool
ifconfig-pool 172.18.19.4 172.18.19.253 
server-ipv6 fc00::/64
keepalive 10 600
management /run/openvpn/openvpn-mgmt-intf unix
push "dhcp-option DNS 1.1.1.1"
push "dhcp-option DNS 8.8.8.8"
ca /config/auth/openvpn/ca.crt
cert /config/auth/openvpn/server.crt
key /config/auth/openvpn/server.key
dh /config/auth/openvpn/dh2048.pem
compat-names

I am attempting to migrate from a working pfsense instance that has:

server 172.18.19.0 255.255.255.0 
server-ipv6 fc00::/64

Why is the nopool option added on the server ip4 statement? While I might manually edit vtun1.conf to remove that option, I assume my changes won’t persist and that is a bad idea. Are there any workarounds to this?

Thanks,
Mike

I’m experiencing this issue as well and there’s not much information about this other than this post. Bumping for interest

It seems to be a bug is server.config.tmpl

If you remove the nopool and ifconfig lines it seems to work, at least in my subnet topology