Bug 216916

Summary:	[handbook] describe corrupt GPT image in USB memstick ver FreBSD 11.0
Product:	Documentation	Reporter:	Jozef Drahovsky <for-freebsd-11>
Component:	Books & Articles	Assignee:	freebsd-doc (Nobody) <doc>
Status:	Closed Not A Bug
Severity:	Affects Many People	CC:	carlavilla
Priority:	---
Version:	Latest
Hardware:	Any
OS:	Any

Description Jozef Drahovsky 2017-02-08 13:51:46 UTC

I suggest adding next text to pages handbook

https://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/bsdinstall-pre.html
2.3.1.1. Writing an Image File to USB
Procedure 2.1. Using dd to Write the Image

# dd if=FreeBSD-11.0-RELEASE-amd64-memstick.img of=/dev/da0 bs=1M conv=sync
# gpart show da0
=>      3  1433741  da0  GPT  (7.3G) [CORRUPT]
        3     1600    1  efi  (800K)
     1603      125    2  freebsd-boot  (63K)
     1728  1429968    3  freebsd-ufs  (698M)
  1431696     2048    4  freebsd-swap  (1.0M)
# gpart recover da0
# gpart show da0
=>       3  15335413  da0  GPT  (7.3G)
         3      1600    1  efi  (800K)
      1603       125    2  freebsd-boot  (63K)
      1728   1429968    3  freebsd-ufs  (698M)
   1431696      2048    4  freebsd-swap  (1.0M)
   1433744  13901672       - free -  (6.6G)

Notes: GPT partition in USB is default corrupted because every USB is differently size. GPT partition is at begin and at end. Command gpart recover da0 writes identical information from begin at the end. Some HW refuse booting with corrupt GPT.

Comment 1 Sergio Carlavilla Delgado freebsd_committer

2023-07-17 17:29:24 UTC

Thanks for the input, but fixing a USB partition table is not within the scope of the handbook.

For a case like this it would be better to look at the manual page