If you've set up NX Server on CentOS 5.5 by downloading it directly from the NoMachine website, and you try to connect to your newly minted install using SSH and a DSA key, and you encounter a problem where the server gives you a message something like this:
NX> 203 NXSSH running with pid: NNNN
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: NNN.NNN.NNN.NNN on port: 22
NX> 202 Authenticating user: nx
NX> 208 Using auth method: publickey
NX> 204 Authentication failed.
Check to make sure that you have synchronized the name of the authorized_keys file in the NX server.cfg, node.cfg and your sshd_config files. I discovered that server.cfg and node.cfg were looking for authorized_keys2 and the sshd_config was looking for authorized_keys. Match those values and restart the server (as described here) and you should have better luck. Apparently, authorized_keys2 was deprecated a long time ago.
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