Fwd: Questions about residual data in LVM after delete the Logic Volume

[Young Yang <afe.young@gmail.com>]

---------- Forwarded message ----------
From: Young Yang <afe.young@gmail.com>
Date: Thu, Nov 26, 2015 at 4:20 PM
Subject: Questions about residual data in LVM after delete the Logic Volume
To: linux-lvm@redhat.com

Hi

This is my LVM version

stack@DevStackOSDomU:~$ sudo lvm version
  LVM version:     2.02.98(2) (2012-10-15)
  Library version: 1.02.77 (2012-10-15)
  Driver version:  4.27.0

I created a 1GB physical volume with a block device setup by losetup,  and added it to my volume group.

Then I created a 1GB logic volume  A  and  I can find my block device here /dev/stack-volumes-lvmdriver-1/volume-e31af77b-1bf4-43e3-ac1f-23e3e825e576. 

I mount this Logic volume and write some data containing a string PATTERN  into it.

Then I grep the block device with  `sudo grep -zbl PATTERN /dev/stack-volumes-lvmdriver-1/volume-e31af77b-1bf4-43e3-ac1f-23e3e825e576`  and   It really have found the string  PATTERN

Then I deleted this 1GB logic volume A  and created another  1GB logic volume.B.

I expected  the residual data containing string PATTERN should appear in the 1GB logic volume B, because they both used all the same 1GB physical volume.

However, when I grep the  1GB logic volume B's block device directly,  it return nothing.

So Here comes the quesions,

Does LVM have any mechanism to prevent the residual data in the previously deleted logical volume from  appearing in the new logical volume?  

If there is any, how can I config it?  How  does it work , where can I find the related  docs? 

Thanks in advances  :)

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