My company is trying to install CentOS 5.3 x64 on to a 3TB RAID6 volume that was configured using a ServeRaid 8k on an IBM x3650. The problem we keep running into is that the anaconda installer see's that the disk is 3TB and then rewrites our msdos partition table as GPT. This is unacceptable as our server is not Itanium nor does it have EFI.
We tried reverting the changes to the partition table made by anaconda using dd to zero out the first 64 and last 9000 sectors on the disk. After that we used fdisk to create a partition structure:
Model: ServeRA SERVER (scsi)
Disk /dev/sda: 3000GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Number Start End Size Type File system Flags
1 32.3kB 518MB 518MB primary ext3 boot
2 518MB 1469GB 1468GB primary lvm
3 1469GB 3000GB 1532GB primary lvm
Unfortunately, anaconda isn't able to recognize the msdos partition table when the installer is restarted and it only gives us the option to try and clear the partition table, resulting in the disk being partitioned using GPT again.
The only reason I think that I am able to get around using GPT is because another server in our office with the same specs is running CentOS fine using the same partition layout. Any pointers or advice would be appreciated. We would like to avoid having to use GPT for the 3TB volume and then a separate device for /boot.