ssh between cygwin and debian wheezy

debug1: ssh_ecdsa_verify: signature correct debug1: SSH2_MSG_NEWKEYS sent debug1: expecting SSH2_MSG_NEWKEYS debug1: SSH2_MSG_NEWKEYS received debug1: Roaming not allowed by server debug1: SSH2_MSG_SERVICE_REQUEST sent debug1: SSH2_MSG_SERVICE_ACCEPT received debug1: Authentications that can continue: publickey,password,keyboard-interactive debug1: Next authentication method: publickey debug1: Offering RSA public key: /home/A/.ssh/id_rsa debug1: Authentications that can continue: publickey,password,keyboard-interactive debug1: Trying private key: /home/A/.ssh/id_dsa debug1: Trying private key: /home/A/.ssh/id_ecdsa debug1: Trying private key: /home/A/.ssh/id_ed25519 debug1: Next authentication method: keyboard-interactive debug1: Authentications that can continue: publickey,password,keyboard-interactive debug1: Next authentication method: password

May 17 09:48:44 a sshd[4337]: Received SIGHUP; restarting. May 17 09:48:44 a sshd[4386]: Set /proc/self/oom_score_adj from -1000 to -1000 May 17 09:48:44 a sshd[4386]: debug1: Bind to port 22 on 0.0.0.0. May 17 09:48:44 a sshd[4386]: Server listening on 0.0.0.0 port 22. May 17 09:49:43 a sshd[4386]: Received SIGHUP; restarting. May 17 09:49:43 a sshd[4417]: Set /proc/self/oom_score_adj from -1000 to -1000 May 17 09:49:43 a sshd[4417]: debug1: Bind to port 22 on 0.0.0.0. May 17 09:49:43 a sshd[4417]: Server listening on 0.0.0.0 port 22. May 17 09:49:43 a sshd[4417]: debug1: Bind to port 22 on ::. May 17 09:49:43 a sshd[4417]: Server listening on :: port 22. May 17 09:58:23 a sshd[4417]: Received SIGHUP; restarting. May 17 09:58:23 a sshd[4491]: Server listening on 0.0.0.0 port 22. May 17 09:58:23 a sshd[4491]: Server listening on :: port 22.

Answers

The client does not display messages like "failed to authenticate using method 'publickey' and the such-and-such key" so to propetly debug this problem follow this checklist on your Debian server:

Make sure the permissions of the ~/.ssh directory of your user is not too permissive.

It should typically be owned by user:user (where user is the name of your user on the server) and have 0700 permission bits set on it.
Make sure the ~/.ssh/authorized_keys file is user:user and 0600.
Edit /etc/ssh/sshd_config (notice the letter "d"—you need the server's configuration file) and raise its logging level:
```
LogLevel DEBUG
```
Save the file and reload the server's configuration:
```
# service ssh reload
```
Now perform another login attempt and inspect what sshd wrote to /var/log/auth.log.
Restore the LogLevel setting to its standard value, INFO, and reload the configuration once again.

kostix

Posted 2014-05-16T17:01:45.427

Reputation: 2 435

I've done this. In question UPD there is log. But nothing changed even logging. – user3003873 – 2014-05-17T06:05:14.250

PS after new attempt it was created known_hosts file in servers ~/.ssh/ – user3003873 – 2014-05-17T06:19:28.523

UPDi tried to connect with command "ssh -vvv" in cygwin and saw strokes "debug3 Incorrect RSA1 identifer" and "debug3 Couldnt load "/home/A/.ssh/id_rsa" as RSA publick key" – user3003873 – 2014-05-17T06:27:37.327

@user3003873, it looks you've got a malformed private key. Try doing ssh-keygen -f /path/to/id_rsa -y to verify the key is OK (this command derives and prints the public key from the specified private key). – kostix – 2014-05-17T21:06:32.600

@user3003873, one more question: are you sure you have an RSA key, and not DSA? What options did you use to generate the key? – kostix – 2014-05-17T21:07:24.423

ssh-keygen -t rsa - I am sure because didnt change namee of key - and default if_rsa is by RSA. Sure? – user3003873 – 2014-05-18T03:24:43.090

@user3003873, what's with my first comment? Did you verify the key's integrity? I'm not sure about the default because I don't know if this default is built-in (in OpenSSH) or selected at build time or can be configured on a particular system. On Debian, it seems to be RSA. – kostix – 2014-05-18T08:00:24.400

Yes, I rechecked and it was realy something wrong with keys, but now corrected that, but with the same result. Also, tried to shh to localhost on win7 and deb it works, and on deb it put smth in auth.log, but when I try to connect from win7 to deb, nothing is written in log. – user3003873 – 2014-05-18T10:48:54.213

For the future, notice that SSH has the ssh-copy-id program which takes care of properly adding your local public key to the list of authorized keys for your user on the target server. For it to work, another auth method has to work at the time you're using it -- such as keyboard-interactive. – kostix – 2014-05-16T17:49:01.267

Of course, I tried ssh-copy-id firstly - no result, so I did it handy. I need pnly keys, no pass interactive. – user3003873 – 2014-05-16T20:06:38.547