Re: [PATCH] mkfs.btrfs: allow UUID specification at mkfs time

[Duncan <1i5t5.duncan@cox.net>]

Brendan Hide posted on Wed, 14 May 2014 14:25:22 +0200 as excerpted:

> On 14/05/14 09:31, Wang Shilong wrote:
>> On 05/14/2014 09:18 AM, Eric Sandeen wrote:
>>> Allow the specification of the filesystem UUID at mkfs time.
>>>
>>> (Implemented only for mkfs.btrfs, not btrfs-convert).
>> Just out of curiosity, this option is used for what kind of use case?
>> I notice Ext4 also has this option.:-)

> Personally I can't think of any "average" or "normal" use case. The
> simplest case however is in using predictable/predetermined UUIDs.

AFAIK the most common use-case would be when redoing filesystems already 
listed in fstab with UUID= mounting.

I use and prefer LABEL= instead of UUID= mounting here, but I commonly 
keep a working and at least one identically sized partition backup 
filesystem copy of all non-throw-away filesystems, with fstab entries for 
both the working and backup versions, and periodically do a mkfs and 
recopy of the backup, with occasional boots to the backup and mkfs and 
recopy of the working version as well.  As I use LABEL= fstab entries I 
ensure that I specify the same label at mkfs time so I don't have to redo 
the fstab, and people that use UUID= fstab entries would find the ability 
to specify UUID at mkfs time as useful as I do the ability to specify 
label. =:^)

Many grub2 configurations also uses UUID so the same idea applies there.

-- 
Duncan - List replies preferred.   No HTML msgs.
"Every nonfree program has a lord, a master --
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