How to connect to a server using another server by ssh in shell script?

Question

The scenario is like:

SERVER_A="servera.com"
SERVER_A_UNAME="usera"
SERVER_B="serverb.com"
SERVER_B_UNAME="userb"

I want to write a shell script which will fist connect to server A, and then only it would be connected to server B. Like:

#!/bin/sh
ssh $SERVER_A_UNAME@$SERVER_A ...and then
ssh $SERVER_B_UNAME@$SERVER_B

But I am not able to do it. It does connect to server A only. How can I achieve it?

Why do you have to automate accessing a remote server through another server? — konsolebox, Sep 03 '13 at 16:41
What do you want to do on server B? Do you want to have an interactive shell session or do you have some specific commands to run non-interactively? — glenn jackman, Sep 03 '13 at 17:20
Yes...I want to have an interactive shell session on server B. — Workonphp, Sep 04 '13 at 04:57

score 0 · Answer 1 · edited May 23 '17 at 10:31

0

You may be able to find some help with this previous question:

How to use bash/expect to check if an SSH login works

Depending on your situation you might also to execute an remote ssh command and wait for positive feedback.

See:

How to use SSH to run a shell script on a remote machine?

edited May 23 '17 at 10:31

Community

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answered Sep 03 '13 at 16:09

bakercp

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score 0 · Answer 2 · answered Sep 03 '13 at 17:32

you should have a look at ssh ProxyCommands that lets you do indirect connects automatically. basically you put the following in you .ssh/config

Host gateway1
  # nichts

Host gateway2
  ProxyCommand ssh -q gateway1 nc -q0 gateway2 22

Host targethost
  ProxyCommand ssh -q gateway2 nc -q0 targethost 22

and then you can run ssh targethost successfully even if targethost is not reachable directly. you can read more about this e.g. here http://sshmenu.sourceforge.net/articles/transparent-mulithop.html

How to connect to a server using another server by ssh in shell script?

2 Answers2