Re: Linux mdadm superblock question.

From: Michael Evans
Date: Sat Feb 13 2010 - 23:02:45 EST


On Sat, Feb 13, 2010 at 5:51 PM, Volker Armin Hemmann
<volkerarmin@xxxxxxxxxxxxxx> wrote:
>>0.90 has a very bad problem, which is that it is hard to distinguish
>>between a RAID partition at the end of volume and a full RAID device.
>>This is because 0.90 doesn't actually tell you the start of the device.
>>
>>Then, of course, there are a lot of limitations on size, number of
>>devices, and so on in 0.90.
>
> but it is the only format supporting autodetection.
>
> So - when will autodetection be introduced with 1.X? And if not, why not?
>
> All I found was 'autodetection might be troublesome' and nothing else.
>  But dealing with initrds is troublesome too. Pure evil even.
>
> Glück Auf,
> Volker
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I remember hearing that 1.x had /no/ plans for kernel level
auto-detection ever. That can be accomplished in early-userspace
leaving the code in the kernel much less complex, and therefore far
more reliable.

In other words, 'auto-detection' for 1.x format devices is using an
initrd/initramfs.
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