NSD

NSD uses BIND-style zone-files (zone-files used under BIND can usually be used unmodified in NSD, once entered into the NSD configuration).

NSD uses zone information compiled via zonec into a binary database file (nsd.db) which allows fast startup of the NSD name-service daemon, and allows syntax-structural errors in Zone-Files to be flagged at compile-time (before being made available to NSD service itself).

The collection of programs/processes that make-up NSD are designed so that the NSD daemon itself runs as a non-privileged user and can be easily configured to run in a Chroot jail, such that security flaws in the NSD daemon are not so likely to result in system-wide compromise as without such measures.

As of May 2018, four of the Internet root nameservers are using NSD:

• k.root-servers.net was switched to NSD on February 19, 2003.
• One of the 2 load-balanced servers for h.root-servers.net (called "H1", "H2") was switched to NSD, and now there are 3 servers all running NSD (called "H1", "H2", "H3").
• l.root-servers.net switched to NSD on February 6, 2007.
• d.root-servers.net was switched to NSD in May 2018.

Several other TLDs use NSD for part of their servers.