Check status of one port on remote host [closed]

Answer 1

In Bash, you can use pseudo-device files which can open a TCP connection to the associated socket. The syntax is /dev/$tcp_udp/$host_ip/$port.

Here is simple example to test whether Memcached is running:

Here is another test to see if specific website is accessible:

$ echo "HEAD / HTTP/1.0" > /dev/tcp/example.com/80 && echo Connection successful.
Connection successful.

For more info, check: Advanced Bash-Scripting Guide: Chapter 29. /dev and /proc.

Related: Test if a port on a remote system is reachable (without telnet) at SuperUser.

For more examples, see: How to open a TCP/UDP socket in a bash shell (article).