Poison Pill is an open-source remediation system that runs as a Daemonset - a pod per node, which reboots unhealthy nodes.
Node Healthcheck Operator (or any other operator that supports the external remediation API) will create a
PoisonPillRemediation custom resource for an unhealthy node. The Poison Pill agent will reboot once this custom resource exists.
As opposed to other remediation systems, Poison Pill does not require any management interface (e.g. IPMI etc.) or an API to node provisioning.