The HS20 is a pretty standard x86 blade, its nothing fancy or even interesting.. Only thing you need to take note of is the fakeraid , see below.
As a start I will update the BIOS. HS20-8832 BIOS
IBM have a BIOS update CD for this, I will be using :- "ibm_fw_bios_bse127a_anyos_i386.iso". The update process is just a menu driven system. It's quite easy and simple.
So insert the Gentoo minimal boot cd. Select the correct blade and media owner.
When booting gentoo you need the following to make use of the wack fakeRAID. At the gentoo boot: prompt enter the following
This will create a device under "/dev/mapper" will be a control file and a LSI_xxxxxxx file, where xxxxx is a whole bunch of letters. This is your fakeRAID device.
The HS 20 uses LSI "megaraid IDE" for some reason the device ID's as set as braodcom, "00:0f.1 RAID bus controller: Broadcom CSB6 RAID/IDE Controller (rev b0)" I am still at a loss as to why IBM rebadge an LSI chip as a braodcom! What ever, its supported by dmraid who cares.
So lets get into the install.
Partition you disk how ever you like apart from a separate boot partition on each disk, this must be non fake raid partition. After this you must use the /dev/mapper, otherwise you will see two physical disks. For me this is :
# fdisk /dev/mapper/lsi_ejbeghcgea
Follow the handbook as per normal for a stage3 install. Apart from your /etc/fstab file and kernel support for the fakeRAID device.