BL20p G2 wont boot from logical drive

[rossb2]

BL20p G2 had a hard drive failure, there are 2 disks in the array. Connected to the ILO and saw the blade attempting to boot from NIC. It is aparrent the array failed.

I took out the failed hard drive from the upper HD slot and replaced it with a spare drive from a decomissioned server(used drive). On doing this a second logical drive was added to the disk contoller.(I regret adding the used drive at this point).

Booted array configuration utility and deleted the logical drive & array created by the new drive in the uppper slot.

I removed the new drive, left the orignal drive in the lower slot and trued to boot from the logical drive(listed as logical drive 2 RAID 0). It doesnt boot. Smartstart lists an issue as "no bootable drive configured".

I appreciate that I added the replacement drive too early. I am wondering
-why did the array initially fail with 1 working drive left
-is there any way I can get the remaining logical drive bootable without a new logical drive and OS rebuild.

[rossb2]

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