Showing posts with label PPC. Show all posts
Showing posts with label PPC. Show all posts

Friday, 23 September 2011

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