#24 On/off parameter for SSH tunneling

[Ralph Altenfeld]

Hi Borek,

I like to propose a switch to disable the SSH tunneling in the corresponding methods, e.g. AllocateJobWithJobmanager.

In trusted networks, this kind of encrypted data transfer might not be necessary. A disabling opportunity would ease the setup and reduce the platform overhead.

My inofficial reason to propose it, is the easier way to debug a remote interface. No hanging SSH tunnels to kill each time ... ;)

Regards,
Ralph

[Vit Smilauer]

Hi Ralph,
I use the approach already defined in
def sshTunnel(remoteHost, userName, localPort, remotePort, sshClient='ssh', options='', sshHost='', Reverse=False)

setting sshClient='manual' creates no SSH tunnels. A user has to open/close the tunnel externally. The argument sshClient enters allocateApplicationWithJobManager() or allocateNextApplication() and is passed further to sshTunnel().

You may check this funcionality in Example06-JobMan/scenario.py when setting cConf.sshClient='manual'.

Vit & Borek

[Ralph Altenfeld]

I was thinking of a scenario without SSH tunneling at all and with using the job manager functionality.

Ralph

[Vit Smilauer]

Dear Ralph,
I got your point. I modified both examples Example06 and Example06-JobMan so no ssh tunnels are created. You can check that functionality if you turn in both server/client scripts an option noSSH=True. This means in principle two things:

• both server's IP and serverNathost's IP must equal to '127.0.0.1'. We stay now on one local machine.
• serverPort and serverNATport must be the same so an application requests the same port as running server's daemon.
• in case of JobManager, one connection goes to JobManager according to the items above. Since JobManager assigns a new communication for a new job, port of job's daemon needs to be passed to an application. This could be done easily when passing jobNatport = -1 so JobMan2cmd.py synchronizes daemon's port with allocated port. Look in Example06-JobMan/scenario.py.

You should adapt your codes easily according to Example06-JobMan, changing a few lines with different arguments. You have this 0.20.08 version in both git and pip. Hope it helps. Vit

[Ralph Altenfeld]

Ok, it works locally ( i.e. Example06_JobMan ). That's sufficient for developing or debugging.
But it seems not to work remotely. Still an SSH tunnel was tried to set up in that case.
Ralph