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I reinstalled a server which was obsolete for its normal business. There is a RAID controller inside with 2 HDD's (80GB each, with Ubuntu 12.04.2 Server installed) and 4 SSD's (32GB each) with a Logical Volume on the SSD's (sdb). After removing the Logical Volume by entering the following command (it seems the LVM wasn't removed with the installer):

$ dmsetup remove /dev/mapper/data-mysql

But now I can't do any real stuff with the SSD's on sdb. When I enter 'fdisk -l' in the terminal, it waits a few seconds and print the following errors:

end_request: I/O error, dev sdb, sector [32|72|96]
Buffer I/O error on device sdb, logical block [4-16]

The SSD's are working properly before so my guess is they are not broken. At the moment I can not even install grub on sda as I get the same errors.

Does anyone know how to fix this problem? There is still a directory or file in /dev/mapper, but it is 'control' and it seems it can't be removed by dmsetup.

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