What it does
dnsi is NLnet Labs' command-line DNS inspection tool, with query and lookup commands and a comparison of resolver and authoritative responses.
Use query for a chosen nameserver or the system resolver, and lookup for address-to-name or name-to-address work. NLnet Labs also documents comparing a resolver’s answer with the authoritative answer for the same question, which helps investigate a change that appears stale. Per-command help is available in full and summary forms. The official README lists particular Debian, Ubuntu and RHEL-compatible binary packages; source builds require Rust 1.78 or newer in the version read. Check the current package and command documentation before scripting against it: the publisher calls dnsi an early-stage tool. Its source is identified as BSD-3-Clause licensed.
Strengths
- Resolver/authoritative answer comparison
- Forward and reverse lookup commands
Watch out for
- The publisher labels the utility early stage
Sources
- NLnet Labs - domain - dnsi (Oct 26, 2026)
- dnsi official README package, help and build scope (Oct 26, 2026)