Creating A Complex Raid 10 With Mdadm - Novell LINUX ENTERPRISE SERVER 10 - STORAGE ADMINISTRATION GUIDE 7-2007 Administration Manual

The procedure in this section uses the device names shown in the following table. Make sure to
modify the device names with the names of your own devices.
Scenario for Creating a RAID 10 (0+1) by Nesting
Table 7-4
Raw Devices
/dev/sdb1
/dev/sdc1
/dev/sdd1
/dev/sde1
1 Open a terminal console, then log in as the root user or equivalent.
2 Create 2 software RAID 0 devices, using two different devices for each RAID 0 device. At the
command prompt, enter these two commands:
mdadm --create /dev/md0 --run --level=0 --chunk=64 --raid-devices=2
/dev/sdb1 /dev/sdc1
mdadm --create /dev/md1 --run --level=0 --chunk=64 --raid-devices=2
/dev/sdd1 /dev/sde1
The default chunk size is 64 KB.
3 Create the nested RAID 0+1 device. At the command prompt, enter the following command
using the software RAID 0 devices you created in
mdadm --create /dev/md2 --run --level=1 --raid-devices=2 /dev/md0 /
dev/md1
4 Create a file system on the RAID 0+1 device /dev/md2, such as a Reiser file system
(reiserfs). For example, at the command prompt, enter
mkfs.reiserfs /dev/md2
Modify the command if you want to use a different file system.
5 Edit the /etc/mdadm.conf file to add entries for the component devices and the RAID
device /dev/md2.
6 Edit the /etc/fstab file to add an entry for the RAID 0+1 device /dev/md2.
7 Reboot the server.
The RAID 0+1 device is mounted to /local.

7.3 Creating a Complex RAID 10 with mdadm

Section 7.3.1, "Understanding the mdadm RAID10," on page 86
Section 7.3.2, "Creating a RAID10 with mdadm," on page 88
RAID 0 (stripe)
/dev/md0
/dev/md1
Step
RAID 0+1 (mirrored stripes)
/dev/md2
2:
Managing Software RAIDs 6 and 10 with mdadm 85