How to probe early-boot with systemtap (dracut-based systems) Updated 2018-07-24T15:31:51+00:00 This article aims to provide a general overview with simple example on how to use systemtap probes during early-boot of a system. NOTE: This feature is only applicable for dracut-based systems! Subscriber content preview. For full access to the Red Hat Knowledgebase, please log in.Not a subscriber? Learn more about the benefits of Red Hat Subscriptions.