ssh localhost connection closed by 127.0.0.1? - ssh

Question

So, I'm going through this tutorial (Running Hadoop on windows using cygwin...) to setup hadoop on my WINDOWS (please don't ask why I would use Linux). So I got to this point that I need to SSH to my localhost and test the SSH using Cygwin, but it closes the connection and says:
Connection closed by 127.0.0.1
I've googled a lot but couldn't find any proper answer for my problem.
P.S.: I'm running cygwin on Windows 7 professional x64
any idea?
BTW, Here is a sample run:
$ ssh -v localhost
OpenSSH_6.0p1, OpenSSL 1.0.1c 10 May 2012
debug1: Reading configuration data /etc/ssh_config
debug1: Connecting to localhost [127.0.0.1] port 22.
debug1: Connection established.
debug1: identity file /home/Soroush/.ssh/id_rsa type 1
debug1: identity file /home/Soroush/.ssh/id_rsa-cert type -1
debug1: identity file /home/Soroush/.ssh/id_dsa type -1
debug1: identity file /home/Soroush/.ssh/id_dsa-cert type -1
debug1: identity file /home/Soroush/.ssh/id_ecdsa type -1
debug1: identity file /home/Soroush/.ssh/id_ecdsa-cert type -1
debug1: Remote protocol version 2.0, remote software version OpenSSH_6.0
debug1: match: OpenSSH_6.0 pat OpenSSH*
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_6.0
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug1: kex: server->client aes128-ctr hmac-md5 none
debug1: kex: client->server aes128-ctr hmac-md5 none
debug1: sending SSH2_MSG_KEX_ECDH_INIT
debug1: expecting SSH2_MSG_KEX_ECDH_REPLY
debug1: Server host key: ECDSA 19:2d:f6:84:4d:e5:0d:d4:5e:e6:e5:a4:6a:3c:ea:8b
debug1: Host 'localhost' is known and matches the ECDSA host key.
debug1: Found key in /home/Soroush/.ssh/known_hosts:1
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/Soroush/.ssh/id_rsa
Connection closed by 127.0.0.1

Answer 1

When you installed Cygwin and ran ssh-host-config, you might have created user cyg_server. So when you are connecting to ssh, you need to use the user cyg_server#localhost.
When you run ssh with that user, it will ask you for the password that you provided when you ran ssh-host-config.
$ ssh cyg_server#localhost
cyg_server#localhost's password:
Last login: Mon Dec 31 01:14:44 2012 from ::1
cyg_server#polorumpus ~
$
I hope it will be useful.

Answer 2

It looks like the key isn't being accepted. Check that /home/Soroush/.ssh/id_rsa.pub has been added to /home/Soroush/.ssh/authorized_keys
I would also check that
RSAAuthentication yes is set in /etc/ssh/sshd_config

Answer 3

I had to do these to fix the problem:
chown <USERNAME> /var/log/sshd.log
chown -R <USERNAME> /var/empty
chown <USERNAME> /etc/ssh*
chmod 755 /var/empty
chmod 644 /var/log/sshd.log
Note that the is my desired user name, not cyg_server.

Answer 4

I Found this post relating to my issue, but it turned out that my cyg_server account did not have administrator privilege.

Answer 5

I had the same problem, and it was generated by Putty authentication agent (Pageant): it was running with a private key. For some reason, it tried to use it to connect to localhost. If I closed Pageant (or removed the key), I could ssh to localhost.
But as I wanted to have Pageant running (to be a client of other ssh servers), I managed to modify the local sshd service, so that it 'ignored' in some way Pageant, to accept connections:
Modify /etc/ssh/sshd_config:
PubkeyAuthentication no
Now, it works

Answer 6

I had to use the 64-bit version of Cygwin to get this to work.