Generic Health Check Framework for systemd
On Fedora Silverblue, IoT or Atomic Host:
rpm-ostree install greenboot greenboot-status greenboot-ostree-grub2 systemctl reboot
Place shell scripts representing health checks that MUST NOT FAIL in the /etc/greenboot/check/required.d directory.
Place shell scripts representing health checks that MAY FAIL in the /etc/greenboot/check/wanted.d directory.
Place shell scripts you want to run after a boot has been declared successful in /etc/greenboot/green.d.
Place shell scripts you want to run after a boot has been declared failed in /etc/greenboot/red.d.
Unless greenboot is enabled by default in your distribution, enable it by running systemctl enable greenboot greenboot-healthcheck greenboot-status.
It will automatically start during the next boot process and run its checks.
When you ssh into the machine after that, a boot status message will be shown.
Directory structure:
/etc
└── greenboot
├── check
│ ├── required.d
│ └── wanted.d
├── green.d
└── red.d
Overall boot success is measured against boot-complete.target.
Ordering of units can be achieved using standard systemd vocabulary.
Create a oneshot health check service unit that MUST NOT FAIL, e.g. /etc/systemd/system/required-check.service. Run systemctl enable required-check to enable it.
[Unit] Description=Custom Required Health Check Before=boot-complete.target [Service] Type=oneshot ExecStart=/usr/libexec/mytestsuite/required-check [Install] RequiredBy=boot-complete.target
Create a oneshot health check service unit that MAY FAIL, e.g. /etc/systemd/system/wanted-check.service. Run systemctl enable wanted-check to enable it.
[Unit] Description=Custom Wanted Health Check Before=boot-complete.target [Service] Type=oneshot ExecStart=/usr/libexec/mytestsuite/wanted-check [Install] RequiredBy=boot-complete.target