requirements.rst

Knot DNS Resource Requirements

Hardware requirements

Knot DNS requirements are not very demanding for typical installations, and a commodity server or a virtual solution will be sufficient in most cases.

However please note that there are some scenarios that will require administrator attention and testing of exact requirements before deploying Knot DNS in production. These cases include deployment for a large number of zones (DNS hosting), a large number of records in one or more zones (TLD) or large number of requests.

CPU requirements

Knot DNS scales with processing power and also with the number of available cores/CPUs.

There is no lower bound on the CPU requirements, but it should support memory barriers and CAS (i586 and newer).

Memory requirements

Knot DNS implementation focuses on performance and thus can be quite demanding for memory. The rough estimate for memory requirements is 3 times of the size of the zone in text format. Again this is only an estimate and you are advised to do your own measurements before deploying Knot DNS into production.

Also note that to ensure uninterrupted serving of the zone, Knot DNS employs a Read-Copy-Update mechanism instead of locking and thus requires twice the amount of memory for the duration of incoming transfers.

Supported operating system

Knot DNS itself is written in a portable way, but it depends on several libraries. Namely userspace-rcu, which could be a constraint when it comes to the operating system support. Knot DNS can be compiled and run on most of UNIX-like systems, such as Linux, *BSD, and OS X.