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A Validating Resolver With Unbound

Resolve domains locally with DNSSEC validation and caching.

LinuxnetworkDNSsecurityLow risk
Run unbound-checkconf to validate the configuration, then start the service.

01Command

Command
$ unbound-checkconf

02What it does

Unbound resolves queries itself and validates DNSSEC, caching results for the whole machine or network. It can be configured for a local stub on 127.0.0.1 or as a full resolver for many clients.

03Risk

RiskLow risk
Requirementssudo apt install unbound
!Warning: An open recursive resolver is abused for amplification attacks; never expose it to the internet without access controls.

04Undo

✓No undo needed — this command does not change persistent state.

05Sources

  • Debian package: unbound
    Debian · vendor-doc · 2026-09-20
    Evidence: Debian packages Unbound, a validating recursive DNS resolver; unbound-checkconf validates its config.
  • Unbound
    Official project · vendor-doc · 2026-09-20
    Evidence: Debian packages Unbound, a validating recursive DNS resolver; unbound-checkconf validates its config.

Last verified: 2026-09-22 · Category: Network

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