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Date: Fri, 20 Sep 2013 13:30:24 +0200
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From: Alessandro MACUZ <alessandro.macuz@gmail.com>
Content-Type: multipart/alternative; boundary=089e013a132a2347e904e6ceff6b
Subject: [linux-lvm] Mirrored LVM volumes and UUID
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Hi all,

I can't seem to find such answer on the net.

I use mirrored volumes and blkid returns the same UUID for the "raid"
volume and the underlying volumes

/dev/mapper/lvm01-root_mimage_0:
UUID="0b88ad6f-34ed-46d6-abe3-eca0d235b353" TYPE="ext4"
/dev/mapper/lvm01-root_mimage_1:
UUID="0b88ad6f-34ed-46d6-abe3-eca0d235b353" TYPE="ext4"
/dev/mapper/lvm01-root: UUID="0b88ad6f-34ed-46d6-abe3-eca0d235b353"
TYPE="ext4"

Then such ID is used in fstab to mount root based... on UUID.

I wonder how fstab knows that it must use /dev/mapper/lvm01-root and not
the others since the three of them share the same UUID, and if by accident
the others can be erroneusly used/mounted.

Has anyone thought of it? Or it's just me?

Alex

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<div dir="ltr">Hi all,<div><br></div><div>I can&#39;t seem to find such answer on the net.</div><div><br></div><div>I use mirrored volumes and blkid returns the same UUID for the &quot;raid&quot; volume and the underlying volumes<br>
<br><div><div>/dev/mapper/lvm01-root_mimage_0: UUID=&quot;0b88ad6f-34ed-46d6-abe3-eca0d235b353&quot; TYPE=&quot;ext4&quot;</div><div>/dev/mapper/lvm01-root_mimage_1: UUID=&quot;0b88ad6f-34ed-46d6-abe3-eca0d235b353&quot; TYPE=&quot;ext4&quot;</div>
<div>/dev/mapper/lvm01-root: UUID=&quot;0b88ad6f-34ed-46d6-abe3-eca0d235b353&quot; TYPE=&quot;ext4&quot;</div></div></div><div><br></div><div>Then such ID is used in fstab to mount root based... on UUID.</div><div><br></div>
<div>I wonder how fstab knows that it must use /dev/mapper/lvm01-root and not the others since the three of them share the same UUID, and if by accident the others can be erroneusly used/mounted.</div><div><br></div><div>
Has anyone thought of it? Or it&#39;s just me?</div><div><br></div><div>Alex</div></div>

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