Checking port available on a remote machine using nc command instead of telnet . Same command can be used to check on a remote server as well, change the 127.0.0.1 with IP address of the server. Single Port Check nc -zv 127.0.0.1 80 Range of ports: nc -zv 127.0.0.1 20-30 Output : root@server ~]# nc -zv 127.0.0.1 443 Connection to 127.0.0.1 443 port [tcp/https] succeeded! [root@server ~]# nc -zv 127.0.0.1 443-445 Connection to 127.0.0.1 443 port [tcp/https] succeeded! Connection to 127.0.0.1 444 port [tcp/snpp] succeeded! nc: connect to 127.0.0.1 port 445 (tcp) failed: Connection refused [root@server ~]#