Can't you just specify the range as 80 to 81 like so:
nova secgroup-add-group-rule --ip_proto tcp --from_port 80 --to_port 81 webservers default
Can't you just specify the range as 80 to 81 like so:
nova secgroup- add-group- rule --ip_proto tcp --from_port 80 --to_port 81 webservers default