Grub Error 5 after defining new physical Drive with ACU

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HP ML370 G4 SAS SmartArray P400 Raid 5; Linux 

After expanding the Array with 8x 300GB HD's we builded a new logical drive (1 TB) with SmartStart ACU.

After booting I get a GRUB2 error 5, Partition table invalid or corrupt .

Is this a due to hardware limitations? How can I expand the Array?

Thank you for your help!

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After further investigations it seems to happen due to the 2 array controller in the server. Grub is installed on the first controller c0 raid5 which hosts the lvm whereas the second one c1 raid1 has the root & boot directory. A new logical disk on the array controller c0 must change something in the naming of the devices.

So there are 2 possibilities:

changing the position of the controllers 

changing the boot sequence

Any ideas about that? thanks in advance