Check if a port on a remote system is reachable (without telnet)
February 4, 2019 2 Comments
Problem:
I wanted to check if our customer had an issue with network access. I asked him to run telnet command, but because of their security reasons, telnet rpm was not installed at all.
Solution:
One of the solution would be to run nc 🙂 but of course nc was not installed. 🙂
The following command helped me in that situation:
cat < /dev/tcp/192.168.3.4/3260
The port is open if there is no output, but if you receive the following, then the port is closed:
-bash: connect: Connection refused
-bash: /dev/tcp/192.168.3.4/3261: Connection refused