What commands does 'Guided Partitioning' use

[daeron]

what does the installation UI do to a second drive untouched in the UI? Normally I disconnect any non-boot drive before risking use of the installation system but it was after 3 in the morning and I was exhausted. Both boot and data drives were GPT/GUID , the desired boot ufs was set to / (label) and the data drive left alone.
Result is a new system is correctly installed in the ufs partition on the boot drive, and the data drive of ufs partitions is now missing - now being reported as empty and "no such gemo"

 

[Martin Paredes]

FreeBSD use bsdinstall(8), you can check the section 2.6. Allocating Disk Space of the Handbook

Also, you can check the source code of /usr/sbin/bsdinstall, it is a shell script.

What is the output of gpart show ?

 

[SirDice]

what does the installation UI do to a second drive untouched in the UI?

Nothing, nothing at all. Not unless you told the installer to touch it.

Result is a new system is correctly installed in the ufs partition on the boot drive, and the data drive of ufs partitions is now missing - now being reported as empty and "no such gemo"

Was it perhaps encrypted? If the disk is encrypted it would need to be 'unlocked' before you can actually read it.

 

[SirDice]

To add to my last remark, a couple of years ago I decided my server could use a fresh reinstall. Made backups of the various configuration files and proceeded to wipe everything and reinstall. Installation went fine, various things I needed were configured and all was well. Oh, let me check my encrypted, external HD. Erhm. Well fsck! Backed up everything but forgot to backup the encryption key. So now I have an external HD with 2TB of data I can never regain access to. That was a hard lesson to learn.