2012/11/22 - [OS/Ubuntu] - ubuntu server install 후 설정 UFW Allowing IP range - ufw allow proto tcp from xxx.xxx.0.0/xxx.xxx.255.255 to any port 22 - The /24 at the end of the address is the network mask, in CIDR notation. You can look up netmask calculators to figure out what it means, but basically /24 means a netmask of 255.255.255.0 How to configure ufw to forward port 80/443 to internal serve..