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I am trying to connect to NX server from windows client but it reports following exception NX> 203 NXSSH running with pid: 5404 NX> 285 Enabling check on switch command NX> 285 Enabling skip of SSH config files NX> 285 Setting the preferred NX options NX> 200 Connected to address: on port: 22 NX> 202 Authenticating user: nx NX> 208 Using auth method: publickey NX> 204 Authentication failed.

I have regenearted the default_dsa.key on server and imported the same for client but still not working.

Any solutions?

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migrated from Apr 9 '10 at 3:25

This question came from our site for professional and enthusiast programmers.

This knid of thing can have multiple causes; the best bet is to enable detailed logging for your NX server:

  1. Edit /etc/nxserver/node.conf and
    uncomment / change the following:




  2. Make sure user nx can write to /var/log/nxserver.log

  3. Restart the NX server and try logging in from Windows again; you should now have detailed messages in nxserver.log.

/var/log/secure may also have some useful info if you're running into authentication problems.

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IIUC you need to make sure to have the NX public key on the authorized_keys keyring for each user on the NX server itself. run nxserver --usercheck and see if it verifies OK.

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Adding the NX public key as an authorized_keys entry for each user is a security risk, since anyone with the NX private key (i.e. anyone who downloads the NX client) would be able to log in as the user if the authorized_keys file isn't set up correctly. The NX user's file is configured specifically to disallow forwarding and running commands during setup, but when you just add the key to everyone's authorized_keys file, you may not be enabling those same protections. – vicfn Feb 26 '13 at 3:10

It seems like a key problem. Try grabbing the default SSH key of the NX client and using ssh with that key to your NX server. If it fails and you get asked for a password, then it's definitely the keys not matching. Try using ssh-kyegen to create your own custom keys for both the client and the server. Try placing the public key both in NX's configuration directory, and the nx user's .ssh/authorized_keys file. If the custom key works, then try installing the same version of both the client and the server.

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