FreeBSD contributor Allan Jude gives a presentation on ZFS Boot Environments and upgrading remote machines at the latest FOSDEM 19. Click the play button below to tune in:

Using boot environments for atomic in-place upgrades

Describe a system of using ZFS Boot Environments to quickly, safely, and atomically upgrade 100s of remote machines.


  • How the file system hierarchy is modified to allow the systems to be upgraded in-place
  • How we use ZFS to create and deploy the boot environments
  • Simplifying the creation of the BEs using poudriere image
  • Extending poudriere image to support ZFS
  • Using zfsbootcfg to boot a new BE once
  • How we determine if the BE “works” and should be promoted to the default

FreeBSD Papers: ZFS Powered Magic Upgrades

FOSDEM 2019: