System not booting after upgrade 14.3->14.4 with "ZFS: unsupported feature: com.klarasystems: vdev_zaps_v2"

Johan Helsingius <[email protected]> Thu, 30 Apr 2026 11:28:20 +0200

Newsgroups	gmane.os.freebsd.questions
Message-ID	<[email protected]>

Hi all,

Was doing an upgrade from 14.3-R7 to 14.4, and after the freebsd-update
install, the reboot fails with "ZFS: unsupported feature:
com.klarasystems: vdev_zaps_v2"

Any idea what that feature is, and how to recover?

	Julf