I've a IBM bladeserver 8843 with 2 u320 scsi discs, this discs are in an raid 1 array, builded on the onboard mtp raid controller. Worked fine over years. Bescause I need more space for my files on this server I've bought the ibm "storage expansion unit 2" and 2x 300gb u320 scsi discs. The manuall says that I had to activate the 2nd raid controller on the mm but I didn't found it, so I booted my server with appended storage unit and go into the raid bios but I was not able to create a new array as I do it usually on my "big" servers.
Ok so I booted the blade server with the raid cd from ibm which came with the storage expansion unit, in the raid manager it was also not possible to add an new raid array. So I deleted the existing array and tried to create a new one but it was only possible to create one array. Stupid. So I called ibm for help, but the said that my guarantee (and support) ended 3 weeks ago for this server so they can't give me a answer (really cheeky - I've own over 35 ibm servers).
So I offer 500 points for the solution. According to the manual it should be possible. At the moment I builded a raid 1 with the new 300gb dics and run the os from only one onbord disc but thats not good, I need raid 1 safety also for the OS disc.