Conection refused error for telnet and ssh

Question

I try to telnet to one of my systems 172.16.xx.z from 172.16.xx.y, but the response i get is-

sudo telnet 172.16.xx.z

Trying 172.16.xx.z...

telnet: Unable to connect to remote host: Connection refused

Same for localhost-

sudo telnet localhost

Trying ::1...

Trying 127.0.0.1...

telnet: Unable to connect to remote host: Connection refused

And the same experience with ssh:

sudo ssh 172.16.xx.z

ssh: connect to host 172.16.xx.z port 22: Connection refused

Any guesses what could be wrong here? Both my systems run on Ubuntu.

Answer 1

Why do you sudo ssh to connect? You can use ssh client in user mode!

To install ssh server on an Ubuntu box, run

sudo apt-get install openssh-server

Then ssh to that box should work. Telnet is not to be used over the internet due to lack of encryption.

Answer 2

The problem with telnet is that no one runs the telnet daemon on a modern Linux. As for ssh, make sure that sshd is installed and running, and that port 22 is appropriately open on the firewall.