check_ptr_validname

DNS PTR validation check written in C for monitoring systems.

This repository now uses the Naid Astro template as the base for the GitHub Pages site.

What this check does

For a target IP address, the check verifies:

1. PTR lookup success.
2. Hostname validity (strict rules, optional IDN checks).
3. Forward lookup success.
4. Forward-confirm match (resolved IP includes the original input IP).

Exit codes are Nagios/Icinga-compatible:

• 0 OK
• 1 WARNING
• 2 CRITICAL
• 3 UNKNOWN

Build the binary

Requirements:

• C compiler (cc, gcc, or clang)
• make

Build native target:

make

Build Linux x86_64 explicitly:

make OS=linux ARCH=x86_64

Run from CLI

./build/linux-x86_64/check_ptr_validname -i 8.8.8.8 --perfdata

Documentation

Detailed English documentation is available in both repository docs and GitHub Pages routes:

• Code documentation: docs/code.md and /docs/code
• CLI options: docs/cli-options.md and /docs/cli-options
• Integrations (Icinga2, Nagios, CLI): docs/integrations.md and /docs/integrations

Astro website (Naid-based)

Install and run locally:

npm ci
npm run dev

Build static site:

npm run build

GitHub Actions

Deploy GitHub Pages

Workflow: .github/workflows/pages.yml

• Trigger: push to main or manual dispatch
• Builds Astro site and deploys dist/ to GitHub Pages
• Injects repository download links via PUBLIC_* environment variables

Build Linux x86_64 Binary

Workflow: .github/workflows/release-linux.yml

• Trigger: tags matching v* or manual dispatch
• Builds Linux x86_64 binary
• Uploads binary and SHA256 as workflow artifacts
• Creates/updates GitHub release assets for tag builds

Release example:

git tag v1.0.0
git push origin v1.0.0