RHEL Kernel image to large

Interesting issue today in trying to install Redhat 6 on a POWER System, so that if you see this error -


Welcome to yaboot version 1.3.14 (Red Hat 1.3.14-35.el6)
Enter "help" to get some basic usage information
boot: linux
Please wait, loading kernel...
   Elf64 kernel loaded...
Loading ramdisk...
Claim failed for initrd memory at 02000000 rc=ffffffff


Now after some searching on Bugzilla I found what looked like my problem, from this I have done a little testing and resolved the issue as detailed below:


Boot the POWER server and enter the OpenFirmware prompt with selection 8 at the IBM menu on start, then run the following command at the OK prompt -


0 > printenv real-base

If you see the following the I
-------------- Partition: common -------- Signature: 0x70 ---------------
real-base                2000000             2000000


Now if I have understood this correctly the firmware is expecting a image of 32MB and in our case for RHEL6 it is 16MB (or smaller) so we need to set it correctly, as below -


0 > setenv real-base 1000000
0 > printenv real-base
-------------- Partition: common -------- Signature: 0x70 ---------------
real-base                1000000              2000000


Then reboot with a -

0 > reset-all


Then boot of the RHEL image as normal and you should find all install from this point will work OK, in this case it was a virtual server so until the LPAR is removed from the HMC.


Ref -

• 2000000 is 32MB
• 1800000 is 24MB
• 1000000 is 16MB
• c00000 is 12MB