I am trying to setup scp on a new Ubuntu 14.04 system. This system will act as an SSH client to an already configured SSH server on another Ubuntu 14.04 system. I can use putty to SSH into the existing SSH server instance but I am having trouble configuring the new client system with the private key. I am the only user of these systems so I am using the existing private key since it corresponds to the public key already on the SSH server.

On the new client system so far I have added the private key to the ~./ssh/known_hosts file and the /etc/ssh/<username>/authorized_keys file. I have also modified the sshd_config to allow RSA based authentication. When I run my scp command on the client I get this output:

The authenticity of host ' (' can't be established.
ECDSA key fingerprint is 8a:cc:5b:f0:c4:ef:d7:e1:94:67:59:72:8d:a9:60:0b.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added '' (ECDSA) to the list of known hosts.
Permission denied (publickey).
cp: cannot stat ‘user@’: No such file or directory

I originally created the key pair with puttygen. I uploaded the private key file (.ppk) to the client system and used cat to merge the contents into the ~./ssh/known_hosts file which I then copied over to /etc/ssh/user/authorized_keys file. Both of these files are identical with both the public and private keys included. Here is my ssh config:

Host *
SendEnv LANG LC_*
HashKnownHosts yes
GSSAPIAuthentication yes
GSSAPIDelegateCredentials no

I think the problem may be with the ECDSA. It looks like something is calling for ECDSA keys but I am using RSA based keys. Is this the problem? If so, what controls this and how do I change it? One more concern of mine is that the contents of the known_hosts and authorized_keys files appear to be in a putty specific format so I an wondering if that may also be a problem.

  • Please edit your question and include the specific commands you used to generate your keys, how you have modified sshd_config and how you added your key. – terdon Nov 15 '14 at 13:13
  • 1
    did you convert putty ppk to openssh format before merge? – rush Nov 15 '14 at 13:37
  • @rush - not formally no, I did however remove some of the putty specific headers. How would I officially convert? – user53029 Nov 15 '14 at 13:42
  • @user53029, putty key is multiline with headers. if you removed only headers it makes no sense. to convert you can use ssh-keygen -i -f /path/to/ppk/pub – rush Nov 15 '14 at 13:46
  • Getting uudecode failed – user53029 Nov 15 '14 at 13:57

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