[CentOS] raid1 creation :: not large enough to join array
rswwalker at gmail.com
Sat Jan 16 17:35:22 UTC 2010
On Jan 16, 2010, at 11:46 AM, Les Mikesell <lesmikesell at gmail.com>
> Adrian Sevcenco wrote:
>> Ross Walker wrote:
>>> On Jan 16, 2010, at 10:27 AM, Adrian Sevcenco
>>> <Adrian.Sevcenco at cern.ch> wrote:
>>>> I have 2 identical hdd (1002FBYS) with the same firmware, etc ..
>>>> identical! when i try to add the second hdd to this raid1 array i
>>>> the message that /dev/sdb is not large enough to join array!!
>>>> on the first hdd i have 100 mb unpartitioned at the end of disk
>>>> (as i
>>>> understood that mdadm put there some info...)
>>>> Anyone, any idea what can be wrong? i already done this procees
>>>> times and this is first time i encounter this and i have no idea
>>>> can be the problem ..
>>> Make sure the partitions are exactly the same, you can use sfdisk to
>>> copy the table from a to b.
>> well, i was doing raid over device (md_dX) but i found out the
>> problem :
>> even if there are "identical" devices, they have different number of
>> blocks (hdparm output). how is this possible?
>> is there a way to restrict the number of blocks that a hdd have?
>> alternative would be just to clone the first hdd on the "smaller" one
>> and then add the big one to and raid1 array ...
>> Did someone seen this situation?
> I've seen a case where single drive volumes initialized in different
> identical) IBM 3550's with adaptec raid controlers would end up with
> different sizes and wouldn't match up if moved. I think this was a
> bios or
> firmware difference but I'm not exactly sure. I was trying to clone
> disks and
> just started over with the smaller source so it would work everywhere.
Les might be on to something here I remember some BIOS store a per-
device LBA setting which might cause to sizes to differ.
This brings up a good reason to use partitions as it will allow you to
coerce the size down a little 128-256MB so if you need to replace a
drive with a different manufacturer's drive in the future you will
have a better chance in making it fit.
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