Unique ID for UFS?

[Ivan Voras]

Daniel O'Connor wrote:
> Hi,
> I am wondering if there is a unique ID generated for each UFS already? If not 
> would it be possible to add one somehow?
> 
> There is glabel, but I think having a UUID embedded in the FS would be very 
> handy for automation andwould prevent accidents that glabel can cause.
> 
> So, there could be a gfsid module that reads IDs from the FS (NTFS, ext2/3, 
> UFS) and creates device nodes to allow access.

Looking at the output of dumpfs, there is an 64-bit numeric "id" field
that changes from file system to file system so this might it:

magic   19540119 (UFS2) time    Sat Nov 15 04:16:42 2008
superblock location     65536   id      [ 46ea67b4 178d71a1 ]

(but judging from how the value changes on my file systems it might be
related to the timestamp).

If this is a usable ID, it should be trivial to make glabel create IDs
nodes (i.e. /dev/ufs/46ea67b4178d71a1).

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