OpenBSD USB stick installer boot: 7.1 yes, 7.2 no

[psarethi]

A few months ago I'd successfully installed OpenBSD on my laptop. I did it from an image on a USB stick. That was version 7.1

Today I decided to upgrade to 7.2. I decided a clean install was better than an upgrade process, so I downloaded and dd'd an image to a USB stick, just as before. The stick says "No OS" and refuses to do anything.

Tried with 7.1. Stick boots fine.

Tried with 7.2. Stick fails as before.

Tried the 7.2 image in emulation, via qemu. It boots there.

Most unexpected. I've no idea what changed. Has anyone an idea? thank you.

[jggimi]

I'll take a wild guess: you used a media image file with a name that ends with ".iso". These are for optical media only. The image contains a 2048-byte sector CD9660 filesystem that includes an El-Torito optical boot image with OpenBSD's optical bootloader.

For mass storage such as USB sticks, you should use a media image file with a name that ends with ".img". These images have 512-byte sectors, MBRs, and the standard 2-stage bootloader.

If my guess is wrong, you'll need to post more information about your process of obtaining and creating your bootable image.

[psarethi]

Thank you for the reply. That is a mistake I've made in the past, but not this time.

The 7.2 USB image I used is a file named install72.img, which is 696745984 bytes in size and has an sha256sum of 38d796fd50e22201273fda11b753fc66d542abb0a7e61bb39a 928d9c1fc7e8f, which, when I last checked, matched that of the download site. The file was downloaded from http://www.openbsd.org/faq/faq4.html#Download.

The previous, 7.1, USB image is a file name install71.img, which is 696745984 bytes and has a sha256sum of 5aa75092893b4ed969797d2a1f78e3db589004a90847e5457e 5aeb43435d46d3. This file was gotten a while back, so I can't say for certain that it was downloaded from the same page, but odds are, it was.

Were it not for the sha256 check and the fact of it working in qemu, I would have assumed that I'd gotten a corrupt file. Most odd. I wonder, has anyone else successfully booted from the install72.img on non-emulated hardware?

note: The sha256sum for 7.2 was checked against: https://cdn.openbsd.org/pub/OpenBSD/7.2/amd64/SHA256

[shep]

Did you wrtie to a raw device?
https://www.openbsd.org/faq/faq4.html#MkInsMedia

Other thoughts:
Bios settings will only secure boot?
Use gparted -> gdisk to remove gpt/mbr backup partitions, reformat and flash again.
Is the usb drive recognized by last entry in dmesg? I had one usb drive that needed firmware to be recognized and the first dd command overwrote the firmware.

[jggimi]

I just downloaded the amd64 image from the same CDN source. The file is the same length, same checksum:

$ sha256 install72.img 
SHA256 (install72.img) = 38d796fd50e22201273fda11b753fc66d542abb0a7e61bb39a928d9c1fc7e8f3
$ file install72.img 
install72.img: x86 boot sector; partition 1: ID=0xef, starthead 255, startsector 64, 960 sectors; partition 4: ID=0xa6, active, starthead 255, startsector 1024, 1358848 sectors
$ doas vnconfig vnd0 install72.img 
$ doas fdisk vnd0
Disk: vnd0      geometry: 13608/1/100 [1360832 Sectors]
Offset: 0       Signature: 0xAA55
            Starting         Ending         LBA Info:
 #: id      C   H   S -      C   H   S [       start:        size ]
-------------------------------------------------------------------------------
 0: EF      0   0  65 -     10   0  24 [          64:         960 ] EFI Sys
 1: 00      0   0   0 -      0   0   0 [           0:           0 ] unused
 2: 00      0   0   0 -      0   0   0 [           0:           0 ] unused
*3: A6     10   0  25 -  13598   0  72 [        1024:     1358848 ] OpenBSD

I have not (yet) attempted to boot this image.

[jggimi]

And, I've now tested it on a Lenovo T450. The image was written to a USB stick with dd(1) and was booted without issues.

The source of your booting problem is not the image file.

[psarethi]

An update.

I managed to free up a different USB stick. I put the 7.2 OpenBSD image on it as before. This time it booted. The install procedure ran to completion. The resultant installed system booted fine.