Find and delete all snapshots

To find the used snapshot space, run:

zfs list -o space

To delete all ZFS snapshots, run:

zfs list -H -o name -t snapshot | xargs -n1 zfs destroy

Failed to delete dataset: cannot destroy snapshot dataset is busy

zfs holds raid/Dataset@auto-20190405.2100-6m"

raid/Dataset@auto-20190405.2100-6m freenas:repl Mon Jun 13 21:28 2016

zfs release -r freenas:repl raid/Dataset@auto-20190405.2100-6m

KBHost