Let me explain. Using a laptop, I can access a remote cluster user@xxx.xx.xx.xx from anywhere. Once I have accessed this cluster, I can access another one using another_user@yyy.yy.yy.yy. But I cannot directly access the second cluster from my laptop, because it has a firewall that blocks non registered IP's. So, how can I overcome the firewall by ssh tunneling? I googled it, but I did not find a solution.

Connect and open tunnel listening on localhost (laptop) port 2222 :
Then in other session, connect to y.y.y.y server (that is localhost:2222 now):

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As voleg mentioned is still a 2 step process. What you want I do not believe is doable without using 2 steps, unless the firewall permissions are changed. Seeing it is a cluster, there might be data worth protecting, so two step offer better security.

My personal setup is vpn onto lan and then ssh with private keys that are password protected into systems. Really does not take that much longer to do.

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There is ssh's ProxyCommand that might be of use.

Scenario:
Add something like this in your ~/.ssh/config file on your laptop:You should now be able to do ssh target or ssh target.machine.com

The above does assume that netcat/nc is installed on stepping.stone.com

- Stupid SSH Tricks: ProxyCommand
- SSH ProxyCommand

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I could not apply voleg solution because the firewall did not allow me, as ericson007 said. druuna's solution worked fine, however I need something more.

Based on druuna's scenario

+--------+ +--------------------+ +--------------------+
| laptop | ---> | stepping.stone.com | ---> | target.machine.com |
+--------+ +--------------------+ +--------------------+

I need to transfer data between my laptop and 'target.machine.com' using rsync or scp. Since I do not know how to do that directly, I have to transfer data to 'stepping.stone.com' and then to 'target.machine.com'. I have to do that many times a day, which is boring and time wasting. Does anyone know how to overcome this problem? Something like druuna's solution will be very appreciated.

Thanks for your attention!

---------- Post added 11-14-13 at 01:24 PM ----------

I could not apply voleg solution because the firewall did not allow me, as ericson007 said. druuna's solution worked fine, however I need something more.

Based on druuna's scenario

+--------+ +--------------------+ +--------------------+
| laptop | ---> | stepping.stone.com | ---> | target.machine.com |
+--------+ +--------------------+ +--------------------+

I need to transfer data between my laptop and 'target.machine.com' using rsync or scp. Since I do not know how to do that directly, I have to transfer data to 'stepping.stone.com' and then to 'target.machine.com'. I have to do that many times a day, which is boring and time wasting. Does anyone know how to overcome this problem? Something like druuna's solution will be very appreciated.

Thanks for your attention!

Maybe this link will help:

- Using rsync through a firewall (method's 2 and 3 might interest you)

1 members found this post helpful.

Simply perfect!!!

Thanks, Druuna!