DNSViz

DNSViz is a DNSSEC analysis tool for people responsible for domain zones and delegations. It is best suited to administrators and engineers who need to trace validation problems or check proposed DNS changes. Its web interface offers quick analysis, while the command-line suite is the stronger option for repeatable, locally retained work.

Overview

DNSViz maps a domain’s DNSSEC authentication chain and resolution path, then identifies configuration errors. Its graph classifies data as secure, bogus, or insecure according to whether a chain of trust can be established from a trust anchor. That makes it useful for diagnosing where validation breaks, rather than merely reporting a general failure.

The web service remains able to run new analyses, but it is in maintenance mode: it cannot load historical results or save new ones to its database. That is a meaningful constraint for teams wanting a lasting web-based record of changes. The command-line tools can produce local output, making them a better fit when results need to be retained or incorporated into a workflow.

Key features

DNSSEC graph and validation

The graph covers zones, delegations, resource record sets, negative responses, DNSKEY and DS records, NSEC/NSEC3, signatures, CDNSKEY/CDS, wildcards, node status, warnings, and errors. This detail helps an operator follow the authentication chain and inspect the parts of a zone that contribute to a problem. The breadth is valuable for DNSSEC troubleshooting, but the product is focused on that job rather than general network monitoring.

The web visualization uses the root zone KSK as its exclusive default trust anchor; users can configure arbitrary DNSKEY trust anchors in the options field. This supports checks against a chosen anchor, while making the default validation context important to understand before interpreting a result.

Command-line analysis

The suite includes probe, grok, graph, print, and query commands for querying DNS, assessing results, and generating graph or text output. Probe accepts one or more domain names, queries recursive resolvers by default or authoritative servers when requested, and serializes results as JSON. Graph can turn those results into an image, DOT graph, or HTML file. These options suit engineers who want to inspect or preserve analysis outside the web service; they do require comfort with a command line and its dependencies.

DNSViz documents pre-deployment checks for zones and proposed delegation, glue, and DS record changes. That makes it useful before a change goes live, not only when troubleshooting an existing failure.

Pricing

DNSViz is free: the DNSViz plan costs nothing. It is open source under GPL-2.0, with no paid tier or free-trial period. There are no seat or quota terms stated for the plan. The trade-off is not a reduced feature tier but the web service’s inability to save new analyses or retrieve historical ones.

Platforms

DNSViz supports web, API, Linux, macOS, FreeBSD, self-hosted deployment, and other Python-supported environments. Installation is documented through package repositories for Debian, Ubuntu, Fedora, Gentoo, FreeBSD, and specified RHEL and CentOS versions, as well as Homebrew or MacPorts on macOS. A Docker container is also available, with instructions for running DNSViz commands inside it.

Installation has some technical overhead: dependencies include Python, dnspython, pygraphviz, and cryptography, while Graphviz and OpenSSL may need separate installation. Optional GOST DNSSEC algorithm and digest support requires the OpenSSL GOST Engine and M2Crypto. DNSViz is therefore a more natural fit for technically equipped users than for someone seeking a turnkey general-purpose diagnostic app.

Who it's for

DNSViz is a strong fit for DNS administrators, engineers, and others learning or troubleshooting DNSSEC deployment. Its graph makes the chain of trust and resolution path inspectable, and its command-line tools support querying and generating outputs locally. It is less suitable for teams that need the web service to maintain a history of analyses, or for readers looking for broad network diagnostics rather than DNSSEC-focused analysis.

Pros and cons

• Pros: The graph exposes a detailed DNSSEC chain, including records, signatures, status, warnings, and errors, which helps pinpoint validation issues.
• Pros: CLI queries can target recursive resolvers or authoritative servers, and results can be rendered as image, DOT, HTML, or text output.
• Pros: Free, open-source software with web, packaged, container, and self-hosted use options.
• Cons: The web service cannot retrieve historical analyses or save new ones, limiting its use as an ongoing results archive.
• Cons: Local installation depends on a Python stack and may require separately installed Graphviz or OpenSSL, which adds setup work.
• Cons: Its purpose is DNSSEC analysis, so it is not a substitute for broader network monitoring.

Alternatives

For broader network diagnostic needs, browse Network Diagnostic Software. Consider PingPlotter if its connection monitoring fits better: its free plan allows one connection, excludes remote collection, and keeps 10-minute monitoring history; its Professional Edition is $29 a month.

Globalping is another network diagnostic alternative. NetSpot may suit readers comparing other freemium network tools; its free edition is for personal and evaluation use on macOS and Windows. Nmap is a free alternative, with its end-user license excluding redistribution within commercial software or hardware products.

SoftPerfect Bandwidth Manager offers a free Lite plan capped at five rules or streams, with usage reports, a live monitor, and penalties for heavy downloads and uploads. Angry IP Scanner is a free, GPLv2 alternative. Buddi is another free GPLv2 option. RIPE Atlas makes public data freely available, while custom measurements require credits.

Verdict

Choose DNSViz if you need a free, detailed way to diagnose DNSSEC chains, check proposed DNS changes, or generate analysis output from the command line. Its strongest case is the combination of a fine-grained validation graph and flexible local tools. Look elsewhere if you need a web-based history of saved analyses or general network monitoring.