I'm looking to allow SSH access via an IP address range that does not fit neatly into a subnet. Just as an example, 192.168.10.60 thru 192.168.10.80.
I only want a group of so many IPs allowed to SSH to an Ubuntu 16.04 box. This obviously does fit neatly in a subnet, so using 192.168.10.0/24 for 192.168.10.* will allow IPs outside the 60-80 group.
Other than listing each IP address individually, how can a group be allowed? I tried using 192.168.10.60-80 and that did not work. I tried it in /etc/hosts/allow and in /etc/ssh/sshd_config.