[Systemroles] Parameter for hostname or IP address?

The VPN role allows for the user to specify a hostname or an IP address for the connection https://github.com/linux-system-roles/vpn/pull/2#pullrequestreview-538046482 I wanted to open this discussion up to a wider audience. We have some precedence in system roles for a field that can take a hostname or IP address.  The logging role has a field `server_host` in the elasticsearch and relp outputs https://github.com/linux-system-roles/logging/blob/master/README.md#loggi... - The documentation says "Host name" but this can be an IP address.  Also the `target` field for the forwards output - it says "Target host (fqdn)." but it can be an IP address. The metrics role has https://github.com/linux-system-roles/metrics/blob/master/README.md#role-... `metrics_monitored_hosts` which I believe takes IP addresses as well as hostnames. There may be other examples in some of the other roles Does it matter what is the name that the VPN role uses for this field?  Is `host` ok?