I am trying to setup public key authentication on a server running Ubuntu 14.04 by following this post. I have done the following so far :
-
Generated RSA keys on host using
ssh-keygen -t rsa
.The keys (id_rsa & id_rsa.pub ) are now stored in ~/.ssh directory.
-
Copied the keys to server using
ssh-copy-id <username>@<host>
-
Edited /etc/ssh/sshd_config file to add line
PasswordAuthentication no
. -
Restarted ssh with
/etc/init.d/ssh restart
.
Now when I try to ssh from host to server I get the following displayed (I have edited out some details like server address and host names):
$:ssh -v user@domain OpenSSH_6.6.1, OpenSSL 1.0.1f 6 Jan 2014 debug1: Reading configuration data /home/host/.ssh/config debug1: Reading configuration data /etc/ssh/ssh_config debug1: /etc/ssh/ssh_config line 19: Applying options for * debug1: Connecting to domain [192.168.xx.xx] port 22. debug1: Connection established. debug1: identity file /home/host/.ssh/id_rsa type 1 debug1: identity file /home/host/.ssh/id_rsa-cert type -1 debug1: identity file /home/host/.ssh/id_dsa type -1 debug1: identity file /home/host/.ssh/id_dsa-cert type -1 debug1: identity file /home/host/.ssh/id_ecdsa type -1 debug1: identity file /home/host/.ssh/id_ecdsa-cert type -1 debug1: identity file /home/host/.ssh/id_ed25519 type -1 debug1: identity file /home/host/.ssh/id_ed25519-cert type -1 debug1: Enabling compatibility mode for protocol 2.0 debug1: Local version string SSH-2.0-OpenSSH_6.6.1p1 Ubuntu-2ubuntu2.8 debug1: Remote protocol version 2.0, remote software version OpenSSH_6.6.1p1 Ubuntu-2ubuntu2.8 debug1: match: OpenSSH_6.6.1p1 Ubuntu-2ubuntu2.8 pat OpenSSH_6.6.1* compat 0x04000000 debug1: SSH2_MSG_KEXINIT sent debug1: SSH2_MSG_KEXINIT received debug1: kex: server->client aes128-ctr hmac-md5-etm@openssh.com none debug1: kex: client->server aes128-ctr hmac-md5-etm@openssh.com none debug1: sending SSH2_MSG_KEX_ECDH_INIT debug1: expecting SSH2_MSG_KEX_ECDH_REPLY debug1: Server host key: ECDSA 16:00:b8:c5:89:af:e9:50:22:85:76:6d:65:1c:aa:b4 debug1: Host 'domain' is known and matches the ECDSA host key. debug1: Found key in /home/host/.ssh/known_hosts:2 debug1: ssh_ecdsa_verify: signature correct debug1: SSH2_MSG_NEWKEYS sent debug1: expecting SSH2_MSG_NEWKEYS debug1: SSH2_MSG_NEWKEYS received debug1: SSH2_MSG_SERVICE_REQUEST sent debug1: SSH2_MSG_SERVICE_ACCEPT received debug1: Authentications that can continue: publickey debug1: Next authentication method: publickey debug1: Offering RSA public key: /home/host/.ssh/id_rsa debug1: Authentications that can continue: publickey debug1: Trying private key: /home/host/.ssh/id_dsa debug1: Trying private key: /home/host/.ssh/id_ecdsa debug1: Trying private key: /home/host/.ssh/id_ed25519 debug1: No more authentication methods to try. Permission denied (publickey).
I have followed this to fix the issue and did the following :
-
Ensured permissions are not too open by OpenSSH standards.
chmod go-w ~/ chmod 700 ~/.ssh chmod 600 ~/.ssh/authorized_keys
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Created a authorized_keys file in host computer by
ssh-copy-id host@127.0.0.1
and copied the authorized_keys file to the server, changed ownership and permissions as required then.
Still the issue persists. I was able to ssh into the server successfully using password before trying to use Publickey authentication. Has anyone else faced similar issues?
Edit :
There was a new line added to the output when I tried to ssh in later : Agent admitted failure to sign using the key.
. Some googling led to this issue. The issue is called gnome-keyring interference. When I tried SSH_AUTH_SOCK=0 ssh user@domain
I was able to login into the server successfully using publickey authentication. Thank you all for your contribution.
Best Answer
When I tried
ssh -i ~/.ssh/key_name user@domain
there was a response from the server that saidAgent admitted failure to sign using the key.
. This is apparently due to gnome-keyring interference issue and the fix is discussed in this link.A temporary fix is to try
SSH_AUTH_SOCK=0 ssh user@domain
and if with this you can ssh into your server then follow with the fix in the above link.