[ubuntu] md superblock lost, ext4 superblock gone and possibly some moved partitions

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http://ubuntuforums.org – Hello, my server, running Ubuntu 12.04, has two hard drives and a total of seven md raid devices each a mirror on both drives. Last friday it lost a hard disk (/dev/sda) due to faulty hardware. After replacing it, the system came up successfully from the second drive (/dev/sdb). I partitioned it using sgdisk: Code: $ sgdisk -G -R=/dev/sda /dev/sdb After that the system did not boot. The only way to start it was using a rescue system which the hoster provides: Debian GNU/Linux 6.0.2 (squeeze), Linux rescue #1 SMP Mon Jul 25 18:36:18 CEST 2011 x86_64 GNU/Linux and mdadm v3.1 (Hardware)