modd_health is a WHMCS addon that monitors selected hosting products using direct authoritative DNS queries and HTTPS health checks. It records current state in WHMCS, alerts through Google Chat after two matching observations, adds DNS and health information to service pages, and supplies an administrator dashboard widget.
Enter the reproducible development shell and run all checks:
nix-shell --run 'composer install && composer qa && go test -mod=mod ./... && actionlint && shellcheck bin/build-release'Create an installable release locally:
nix-shell --run 'composer install && bin/build-release 1.0.0'The resulting whmcs-modd-health-1.0.0.zip includes the addon, both static Linux checker binaries, and the manifest consumed by WHMCS Plugin Updater.
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Extract the release at the WHMCS root so
modules/addons/modd_healthis created. -
Confirm both files under
modules/addons/modd_health/binare executable by the WHMCS cron user. -
Activate Modd Health under System Settings → Addon Modules and grant access only to appropriate administrator roles.
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Open Addons → Modd Health, assign products to profiles, and configure DNS patterns, permitted IPs, health URLs, database TLS, and the Google Chat webhook.
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Allow the cron host outbound TCP and UDP port 53 to public authoritative nameservers and HTTPS to monitored sites and Google Chat.
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Add this system cron entry, adjusting the paths and PHP binary:
*/6 * * * * /usr/bin/php /path/to/whmcs/modules/addons/modd_health/cron.php >>/var/log/modd-health.log 2>&1
The PHP CLI must permit proc_open, flock, and execution of the bundled checker. The database user needs normal WHMCS table access; credentials and the webhook are transferred only through the checker's standard input and must not be written to logs.
Deactivation deliberately retains mod_modd_health_config and mod_modd_health_state. After taking a database backup and deactivating the addon, permanently remove its data with:
DROP TABLE mod_modd_health_state, mod_modd_health_config;