openshift-docs/modules/microshift-greenboot-included-health-checks.adoc

//Module included in the following assemblies:
//
//* microshift_running_apps/microshift-greenboot-workload-health-checks.adoc

:_mod-docs-content-type: CONCEPT
[id="microshift-greenboot-included-health-checks_{context}"]
= Included greenboot health checks

Health check scripts are available in `/usr/lib/greenboot/check`, a read-only directory in {op-system-ostree-first} {op-system-image} systems. The following health checks are included with the `greenboot-default-health-checks` framework.

* Check if repository URLs are still DNS solvable:
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This script is under `/usr/lib/greenboot/check/required.d/01_repository_dns_check.sh` and ensures that DNS queries to repository URLs are still available.

* Check if update platforms are still reachable:
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This script is under `/usr/lib/greenboot/check/wanted.d/01_update_platform_check.sh` and tries to connect and get a 2XX or 3XX HTTP code from the update platforms defined in `/etc/ostree/remotes.d`.

* Check if the current boot has been triggered by the hardware watchdog:
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This script is under `/usr/lib/greenboot/check/required.d/02_watchdog.sh` and checks whether the current boot has been watchdog-triggered or not.

** If the watchdog-triggered reboot occurs within the grace period, the current boot is marked as red. Greenboot does not trigger a rollback to the previous deployment.
** If the watchdog-triggered reboot occurs after the grace period, the current boot is not marked as red. Greenboot does not trigger a rollback to the previous deployment.
** A 24-hour grace period is enabled by default. This grace period can be either disabled by modifying `GREENBOOT_WATCHDOG_CHECK_ENABLED` in `/etc/greenboot/greenboot.conf to false`, or configured by changing the `GREENBOOT_WATCHDOG_GRACE_PERIOD=number_of_hours` variable value in `/etc/greenboot/greenboot.conf`.