[CentOS] Installing on partitionable RAID arrays

Thu Mar 26 12:12:27 UTC 2009
RedShift <redshift at pandora.be>


Since linux 2.6, the md layer has a feature called partitionable arrays. So instead of having two disks, creating an identical partition table on both and then putting those partitions in RAID 1, you take those two disks and put them in one partitionable RAID 1 array (in mdadm terms, "mdp") and create a partition table on the new RAID device. The advantages are quite clear compared to the old non-partitionable arrays.

My question is, is this supported by CentOS? The GTK installer doesn't provide a way to create such an mdp device and the integrated partitioning tool does not see for example md_d0 when I create it manually from the console.

Another way to get CentOS on such a configuration would be to do everything manually, thus installing the base system by creating the necessary disk allocations and then rpm -i all the required packages to get it to boot. (I've done this before, it's not a big deal, you just need to follow a certain order - I remember documenting it somewhere but forgot). But since this method is probably not officially documented anywhere or even supported I'll most likely won't get any support if this setup were to fail somehow (like when upgrading between minor versions).

I've tried STFW'ing, but searching for centos and partitionable arrays is too ambiguous.


Best regards,

Glenn Matthys