fdisk -E Can Sweep Disk Used by ZFS Without Warning (6412771)

If you use the fdisk -E command to modify a disk that is used by a ZFS storage pool, the pool becomes unusable and might cause an I/O failure or system panic.

Workaround:

Do not use the fdisk command to modify a disk that is used by a ZFS storage pool. If you need to access a disk that is used by a ZFS storage pool, use the format utility. In general, disks that are in use by file systems should not be modified.