Hi everyone, I am trying to add a slave to my DNS setup. I believe I have the keys and everything set up correctly, comparing the new server configuration to the existing slaves. When I run /usr/local/sbin/rndc -s dns01 reload from the master, I get: rndc: connection to remote host closed This may indicate that * the remote server is using an older version of the command protocol, * this host is not authorized to connect, * the clocks are not syncronized, or * the key is invalid. The clocks are synchronized. The master is running 9.5.1-P3. This new slave was running 9.3.something. Via yum I was only able to upgrade to a newer 9.3 or bring it all the way to 9.7.0-P2. I didn't want to compile from source, so these were my two options. So it is now on 9.7.0-P2. The above error was received both before and after the bind upgrade on the slave. The error seems to indicate that the remote server version must have an equal or later version of rndc, which is why I held out hope for upgrading the slave to 9.7.0-P2. Is there any documentation on rndc version compatibility? Because I haven't found any. And I think the version incompatibility is the problem, but I want to make sure before I move forward with the arduous task of upgrading bind on the master and two existing slaves, because they are production and must be upgraded from source, due to an old OS version. For additional information, here is the only information I get on the slave in the log file: 23-Sep-2013 10:39:02.631 general: error: invalid command from x.x.x.x#3491: bad auth (I have replaced the actual IP with x.x.x.x) Thank you for your time and attention.