![]() ![]() The version-0.90 Superblock - the one we're going to use - needs only few KB of disk space. This free space is where mdadm will store the array's metadata, i.e. If you have to perform either a new installation or a migration of an existing non-raid one, you need to reserve some unpartitioned space at the end of your drive. Part 1: Build the array, mount and chroot In this howto we assume that your system has two hard drives, /dev/sda and /dev/sdb. Migrate an existing non-raid CentOS 5 & 6 installation to a partitionable RAID1 system. Install CentOS 5 & 6 on a partitionable RAID1 system from scratch. And when you need to repair a failed RAID volume with the whole hard drive as a RAID component, all you have to do is to insert a new hard drive and run mdadm -add no partitioning or anything else required. If you are installing a system on a partitionable RAID you can use the whole hard drive as a RAID component device, and since RAID1 is a mirror, you will be able to boot your system from any of the drives in case of failure without any additional tricks required to preserve bootloader configuration, etc. Why would you want to have a system installed on a partitionable software RAID1? The dev entries for partitions on partitionable RAIDs are created automatically by mdadm when the volume is assembled. Such RAID volumes get device names like /dev/md_dX and /dev/md_dXpY for partitions on the volume. ![]() So, since mdadm 2.6 it is possible to create partitionable RAID volumes. ![]() Compare this to a true RAID controller which allows you to build one RAID volume which can be partitioned as a regular hard drive. If you needed several filesystems on RAID, you had to setup several RAID volumes, which means that you had to create several exactly identical partitions on each of the drives in the RAID and create several RAID volumes. Short answer: it is a md RAID volume which can be partitioned as a regular hard drive.įor the long time the traditional way of using md RAIDs was to create a separate partition on each drive going into the raid volume, mark these partitions as type 0xfd (linux raid autodetect), build a volume from these partitions, format it to a certain filesystem and use it. What exactly is a software partitionable RAID1? How to install CentOS 5 & 6 on a software partitionable RAID1. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |