Related: FreeBSD bug 211715

# date ; uptime ; freebsd-version ; uname -a
Sun Sep  4 11:01:04 UTC 2016
11:01AM  up 27 mins, 0 users, load averages: 0.39, 0.76, 0.71
10.3-RELEASE
FreeBSD ghostbsd 10.3-RELEASE FreeBSD 10.3-RELEASE #0 r297264: Fri Mar 25 02:10:02 UTC 2016     root@releng1.nyi.freebsd.org:/usr/obj/usr/src/sys/GENERIC  amd64
# gpart show /dev/ada0
=>       34  976773101  ada0  GPT  (466G)
         34          6        - free -  (3.0K)
         40     204800     1  efi  (100M)
     204840  968544256     2  freebsd-zfs  (462G)
  968749096    8019968     3  freebsd-swap  (3.8G)
  976769064       4071        - free -  (2.0M)

# gdisk /dev/ada0
GPT fdisk (gdisk) version 0.8.10

Partition table scan:
  MBR: protective
  BSD: not present
  APM: not present
  GPT: present

Found valid GPT with protective MBR; using GPT.

Command (? for help): p
Disk /dev/ada0: 976773168 sectors, 465.8 GiB
Logical sector size: 512 bytes
Disk identifier (GUID): FFC904D6-728C-11E6-882A-68B599FCDB6A
Partition table holds up to 128 entries
First usable sector is 34, last usable sector is 976773134
Partitions will be aligned on 8-sector boundaries
Total free space is 4077 sectors (2.0 MiB)

Number  Start (sector)    End (sector)  Size       Code  Name
   1              40          204839   100.0 MiB   EF00
   2          204840       968749095   461.8 GiB   A504
   3       968749096       976769063   3.8 GiB     A502

Command (? for help): v

No problems found. 4077 free sectors (2.0 MiB) available in 2
segments, the largest of which is 4071 (2.0 MiB) in size.

Command (? for help): q
# whoami ; pwd
root
/home/ghostbsd
# cd Desktop/
# gpart backup /dev/ada0 > ada0.backup
# gpart destroy -F /dev/ada0
gpart: Device busy
# zpool status
  pool: tank
 state: ONLINE
  scan: none requested
config:

	NAME        STATE     READ WRITE CKSUM
	tank        ONLINE       0     0     0
	  ada0p2    ONLINE       0     0     0

errors: No known data errors
# zpool export tank
ge# geli status
# gpart destroy -F /dev/ada0
ada0 destroyed
# gpart restore /dev/ada0 < ada0.backup
# gpart show
=>     64  3788059  da0  GPT  (14G) [CORRUPT]
       64     1476    1  ms-basic-data  (738K)
     1540     5760    2  efi  (2.8M)
     7300  3780220    3  apple-hfs  (1.8G)
  3787520      600    4  ms-basic-data  (300K)
  3788120        3       - free -  (1.5K)

=>  63  5697  da0p2  MBR  (2.8M)
    63  5697         - free -  (2.8M)

=>     64  3788059  iso9660/GhostBSD  GPT  (14G) [CORRUPT]
       64     1476                 1  ms-basic-data  (738K)
     1540     5760                 2  efi  (2.8M)
     7300  3780220                 3  apple-hfs  (1.8G)
  3787520      600                 4  ms-basic-data  (300K)
  3788120        3                    - free -  (1.5K)

=>  63  5697  gpt/EFI%20boot%20partition  MBR  (2.8M)
    63  5697                              - free -  (2.8M)

=>  63  5697  iso9660/GhostBSDp2  MBR  (2.8M)
    63  5697                      - free -  (2.8M)

=>       34  976773101  ada0  GPT  (466G)
         34          6        - free -  (3.0K)
         40     204800     1  efi  (100M)
     204840  968544256     2  freebsd-zfs  (462G)
  968749096    8019968     3  freebsd-swap  (3.8G)
  976769064       4071        - free -  (2.0M)

# shutdown -h now