How to reinstall HP StoreOnce 2700 OS

Recently I got my hands on dirty cheap HP StoreOnce 2700 Backup solution. I did not have any experience with that line of HP products, but the opportunity was more than good and I got one of those devices.
It is more or less Proliant DL360p G8 with different RAID controller than in standard HP Proliant server.
StoreOnce 2700 comes with Storage p1224 Array Controller that has fixed configuration. There are 4 2TB Seagate SAS (7200rpm) in RAID 5 (I see 5.5TB of usable space) and configuration of hard drives is fixed. You cannot manage drives through Array Manager as you would standard HP Raid controller

It also has custom HP StoreOnce Backup software installed that manages RAID configuration and modes of operation. Just like a NAS device. It is built on Red Hat distro.
I was a bit confused by this software, because there is no option to configure RAID and disks, so I was not sure how would I restore this device in case I needed to replace disks or software crashes and needs reinstall. Read More

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