. but what if the authorized_keys file DOES EXIST ? . you don’t say how to add to it .

Except for this it is a very helpful and well done article..Thank you .

Curt

agree. Every instruction was clear and helpful for a beginner like me

I stumbled across this site as I was trying to find a way to connect to my FreeNAS box from my windows 7 PC. I am trying to shutdown that PC using a batch file after a process is run from my Windows PC.

The process that you have shown in great detail is absolutely marvellous! I was able to connect to my FreeNAS Unix/Linux box using SSH and do the file manipulations etc.

One question though is that whilst I have copied the public key in the authorized_key file on the Unix PC and everything seems to be ok but when I try to connect using the SSH connection, it still asks for my password (that’s possibly because I haven’t yet stopped the access using password authentication) but it doesn’t tell me that its trying to do a ‘public key authentication’ — so I don’t know if its connecting me through password or public key — is there any other way to tell.

Initially, I got the ‘Server refused our key’ but after repeating the process a few times, I don’t get that error but I am still not sure how am I connecting ot my Unix PC?

Can you please advise?

Deepak

It’s been a while since I have done this, but I believe if Password Authentication is enabled, then that is what you will get logged in with. I suspect that if you want to use public key encryption, you need to disable the password auth.

I could be wrong, but try doing that, and let us know what happens.

Thanks for reading, and do please let me know what you find out. I will see if I can look back at this after work tomorrow if you still haven’t got it figured out.

Cheers!

This is what is get when I try to connect with SSH authentication (because I can’t attach the screen dump I will try and simulate what I see on the screen) :-

Using username «anyone».
anyone@192.168.1.3’s password :

I then enter the password and I am logged in

But this is not logging through Public Key Authentication, is it?

Further, when I try to shutdown or reboot that PC, it says permission denied.

Where do I need to change the permissions so that I can do this or how do I log on as root (I assume that root can do that — but there is not password for root at this point)

Deepak

Don’t worry about not being able to shutdown/reboot — can do that now! Had to change the sudoers file on the server. That aspect is ok!

However,I am still not connecting via ssh using public key authentication — I am doing so using password authentication. Is this what is stopping me from connecting via Plink?

How do I disable password authentication? Secondly, if I do that, how would I be log in if the public key authentication doesn’t work? My concern is that I have to eventually connect to this server using a batch file. For that purpose, I have downloaded Plink and made the changes as I have understood from some article available on the net but I am not able to connect as yet through Plink even though I am able to connect via PuTTY.

Deepak

Hmmm. You’re right.

I pretty much walk through how to disable password auth. But you are correct, you really can’t disable that until you know the public key thing is working.

When I was having difficulty with this, it was usually related to properly adding the key to the authorized_keys file, and/or properly setting the permissions.

If you can, download (or copy the text from) your sshd_config file, and your authorized_keys file. Once done, immediately delete the current key, create a new key pair and repeat the key process (because I want you to send me the current key file, and I am just some stranger from the internet!). Really, don’t do this part unless you can immediately change the key out.

Then email both to me at xivsolutions at gmail dot com.

Then I can take a look and see if there is anything you might be doing wrong.

Also, take a series of screen shots showing your putty configuration and send those two.

In both, obviously, redact any confidential info.

I will 100% understand if you’re not comfortable with this, but it’s the only way I can think of to trouble-shoot the situation.

Thanks,
Stephen

Alright — I managed a solution. I simply uninstalled and reinstalled my openssh on the server machine. This did the trick.

S

Good deal man, glad you figured it out!

Sorry I wasn’t able to get back to you, I’m traveling at the moment.

Thanks for reading, and for updating with your solution!

My understanding is that between two Linux boxes, one can use the scp command. There is a brief discussion HERE

Since you are using Putty, with a Windows box and a ‘nix box, you will want to check out the PuTTY User Manual (installed with PuTTY in the PuTTY application directory on your Windows Machine). Check out «Chapter 5, Using PSCP to transfer files securely.» It appears there is some configuration required in order to use pscp this way.

From the PuTTY User Manual:

I have not done this myself yet. However, it basically bridges the scp command between Windows and Linux.

Hope that helps. I may just have to do a post on this, after I mes with it this weekend!

Please do let me know how it goes for you . . .

-J

/ssh_config_backup» is missing the action «cp» to actually copy the configuration file. It should be «$ sudo cp /etc/ssh/sshd_config

Thank you for such an appreciated affort. I will go on and read the next too blogs.

Ha! Nice catch. Ooops. I will update asap!

Thanks for reading! Yes, it was a bit of an undertaking to write out clearly what is a not-too-complicated process. Mainly due to the number of detailed steps involved. Also, I am new to Linux and SSH, so I tried to address the pain points I myself ran into trying to get the job done (online, I found I had to perform multiple searches for different bits of info to get the whole picture in a manner which I could understand).

My next step will be an article explaining how to use the SSH tunnel to remote in to the linux desktop via VNC.