I have a CentOS 6 server with software RAID1 (2x3TB):
- sda
# parted /dev/sda unit s print
Model: ATA TOSHIBA DT01ACA3 (scsi)
Disk /dev/sda: 5860533168s
Sector size (logical/physical): 512B/4096B
Partition Table: gpt
Number Start End Size File system Name Flags
1 2048s 1026047s 1024000s ext4 boot
2 1026048s 5860532223s 5859506176s raid
- sdb
# parted /dev/sdb unit s print
Model: ATA TOSHIBA DT01ACA3 (scsi)
Disk /dev/sdb: 5860533168s
Sector size (logical/physical): 512B/4096B
Partition Table: gpt
Number Start End Size File system Name Flags
1 2048s 1026047s 1024000s ext4 boot
2 1026048s 5860532223s 5859506176s raid
- md[0-1]
# cat /proc/mdstat
Personalities : [raid1]
md0 : active raid1 sdb1[1] sda1[0]
511936 blocks super 1.0 [2/2] [UU]
md1 : active raid1 sdb2[1] sda2[0]
2929621824 blocks super 1.1 [2/2] [UU]
bitmap: 1/22 pages [4KB], 65536KB chunk
unused devices: <none>
- md0 is mounted on /boot
- md1 is used for physical volume with 'root' and 'swap' logical volumes
I would like to use the same partitioning layout on CentOS 7 however anaconda is complaining about missing 'biosboot' partition:
Your BIOS-based system needs a special partition to boot from a GPT disk lable. To continue, please create a 1MB 'biosboot' type partition.
Is there a way to aviod this? I was thinking to create a two separate 'biosboot' partitions on each disk to mirror both HDDs.
Creating a BIOS boot partition on each disk would be fine. If you used automatic partitioning, this is what would happen anyway.
You can (and probably should) also boot the installation with UEFI rather than legacy boot, and a BIOS boot partition is not needed in this case (but you will need an EFI partition).