On 6.09.19 г. 12:27 ч., Anand Jain wrote:
>
> <snip>
>
>> This is intended. Otherwise it's an open avenue for the user to shoot
>> themselves in the foot.
>
> I don't understand how?
>
>> If you know what you are doing and are
>> absolutely sure the original fs is no longer present - then just flush
>> libblkid cache and you'll be able to set the FSID back to the original
>> one.
>>
> <snip>
>
> No no its not about the stale cache holding the original fsid. The use
Then this is worst. UUID, by definition, are Unique. What you want to is
to toss the Unique part, meaning we'll really be left with some sort of
ID. What's more - the UUID is used by libblkid to populate the available
devices so not making it unique can cause subtle bugs.
> case is - a golden copy of the bootable OS image is being used and
> shares the same fsid on multiple hosts.
> Now if you want to mount another copy it for some changes, you need to
> btrfstune -m on the copy. And later if you want to boot it
> successfully, it needs its original fsid back.
>
> HTH, Anand
