The absolute minimum requirement is one machine, but this would require the Atomia DNS Master server and Atomia DNS Bind-DLZ Nameserver to be installed on the same machine which is not recommended.
A more likely scenario would be:
Server running Atomia DNS Master.
Backup replica of the Atomia DNS Master database.
Two or more servers running Atomia DNS Bind-DLZ Nameserver.
For larger installations it is also possible to install Atomia DNS API and Atomia DNS database on separate machines.
The software requirements for the Atomia DNS Master are listed in the Atomia DNS Master server installation instructions and the software requirements for Atomia DNS Bind-DLZ Nameserver are listed in the Atomia DNS Bind-DLZ Nameserver installation instructions.
The Atomia DNS Bind-DLZ Nameserver has been tested using dnsperf ( http://www.nominum.com/services/measurement_tools.php ) on a modest system to see its performance.
With dnsperf running on the same machine as the nameserver, this modest system managed to handle 8609 queries per second.
Atomia DNS can scale to handle large DNS infrastructures both on the back end and in terms of nameservers. To be able to scale and handle many DNS queries you only need to add more nameservers into the system. The load will then be spread across all nameservers.
The Atomia DNS Master doesn't usually have a high load since it is only used to provision changes to the nameservers. To scale the Atomia DNS Master server, the Atomia DNS API and Atomia DNS Database can be installed on separate servers. For higher requirements it is also possible to load balance the API using several servers.
Atomia DNS comes with an API containing functions for administrating DNS settings.
The recommended way is to do a full resync using Atomia DNS Sync. More information about this can be found in the Atomia DNS Sync manual .