UFS I only see /dev/label when i boot into single user mode.

Alain De Vos

Alain De Vos

i did glabel label so the device has a glabel.
I only see /dev/label when i boot into single user mode.
Should i put something in /boot/loader.conf ?

Second , i did gpart modify -l <label_name> and i don't see these either in /dev/
 
Some of the label identifiers may have been turned off in loader.conf:
Code: 
% sysctl kern.geom.label
kern.geom.label.disk_ident.enable: 0
kern.geom.label.gptid.enable: 0
kern.geom.label.gpt.enable: 1
kern.geom.label.ufs.enable: 1
kern.geom.label.ufsid.enable: 1
kern.geom.label.reiserfs.enable: 1
kern.geom.label.ntfs.enable: 1
kern.geom.label.msdosfs.enable: 1
kern.geom.label.iso9660.enable: 1
kern.geom.label.flashmap.enable: 1
kern.geom.label.ext2fs.enable: 1
kern.geom.label.debug: 0
It may get a bit confusing if there's a /dev/gpt/somelabel, /dev/label/mylabel, /dev/ada0p1, /dev/gptid/23452-2452-234524-234234 all essentially pointing to the same partition or disk.
 
SirDice said:
Some of the label identifiers may have been turned off in loader.conf:
Code: 
% sysctl kern.geom.label
kern.geom.label.disk_ident.enable: 0
kern.geom.label.gptid.enable: 0
kern.geom.label.gpt.enable: 1
kern.geom.label.ufs.enable: 1
kern.geom.label.ufsid.enable: 1
kern.geom.label.reiserfs.enable: 1
kern.geom.label.ntfs.enable: 1
kern.geom.label.msdosfs.enable: 1
kern.geom.label.iso9660.enable: 1
kern.geom.label.flashmap.enable: 1
kern.geom.label.ext2fs.enable: 1
kern.geom.label.debug: 0
It may get a bit confusing if there's a /dev/gpt/somelabel, /dev/label/mylabel, /dev/ada0p1, /dev/gptid/23452-2452-234524-234234 all essentially pointing to the same partition or disk.
Click to expand...
For me they are all turned on, yet still the same problem.
I rememerber something about loader.conf.
 
Alain De Vos said:
For me they are all turned on, yet still the same problem.
I rememerber something about loader.conf.
Click to expand...
If I recall correctly, some of them conflicted each other, but sorry, forgot which actually were.

And what's confusing is that, for all (at least most) of them except geom like /dev/ada0*, sanely "mounted" partitions dissappear afterwards.
 
nxjoseph said:
I guess the tunable for that is this?

kern.geom.label.disk_ident.enable
Click to expand...
Looks usual sysctl (or defined as both).
Code: 
% sysctl -aT | grep kern.geom.label.disk_ident.enable
kern.geom.label.disk_ident.enable: 0
% sysctl -aW | grep kern.geom.label.disk_ident.enable
kern.geom.label.disk_ident.enable: 0
%
The former ( sysctl -aT) shows all tunables, and the latter ( sysctl -aW) shows all writable sysctls.
 
Alain De Vos said:
i did glabel label so the device has a glabel.
I only see /dev/label when i boot into single user mode.
Should i put something in /boot/loader.conf ?

Second , i did gpart modify -l <label_name> and i don't see these either in /dev/
Click to expand...
On which device or partition did you run glabel label? That command could damage partition tables or filesystems depending on how you use it. It is a more advanced command suitable for more advanced users.

Note that you can set a label on UFS filesystems with tunefs(8). Those will appear in /dev/ufs.
The most commonly used type of label is actually GPT partition labels which the FreeBSD installer creates by default. You can create/modify GPT partition labels with gpart(8) and they will appear in /dev/gpt.

The reason you see /dev/label only in single-user mode is because of an oddity in GEOM. If you mount a filesystem from /dev/ada0p1, for example, labels for it like /dev/gpt/rootfs or /dev/ufs/myname disappear because the labels lose access to /dev/ada0p1 while it is mounted. If you configure the system to mount from the labels instead of from ada0p1, they will not disappear.
 
SirDice said:
It may get a bit confusing if there's a /dev/gpt/somelabel, /dev/label/mylabel, /dev/ada0p1, /dev/gptid/23452-2452-234524-234234 all essentially pointing to the same partition or disk.
Click to expand...

I think it's important to understand that when you create a persistent label with "glabel label ...", you create a new device that's one sector smaller, so a /dev/label/ device should not be accessed except though the label.


Alain De Vos said:
The partition where i used glabel lablel is not recognised under linux ...
Click to expand...

I don't think any of the GEOM stuff is portable. The only case where I still use glabel is on a physical device that I'm going to put geli on, since that's not portable either.
 
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