Preserve Install

It is the easiest of the methods (default method).

Try to remove all the SAN Disks before initiating the install, so as to avoid deleting the data.

Make sure you a good mksysb image.

Common issues are 0554 when dealing with powerpath . (VERY IMPORTANT)

Do install the drivers first and then upgrade from the service pack.

Use the IBM link below , will solve the issue most of the time.

https://www-304.ibm.com/support/docview.wss?q1=led%20554&dc=DB520&rs=1209&uid=isg3T1000132&context=HW1A1&cs=UTF-8&lang=en&loc=en_US&wv=1