Example Software Raid1 Solution For Fault Tolerance Of Traditional Volumes; Managing Traditional Software Raid1 Devices; Mirroring Partitions - Novell Open Enterprise Server 2 System Administration Manual

5.1.4 Example Software RAID1 Solution for Fault Tolerance of
Traditional Volumes
As an example, consider a server that has five server disks. Four of the disks (0, 1, 3, and 4) are
under 4 gigabytes (GB) and each disk contains a single partition the size of the disk. The fifth disk
(5) is 20 GB and contains four partitions of 4 GB each; the remaining 4 GB capacity are unused free
space. Each physical NetWare partition is further subdivided into eight volume segments of about
500 MB each. The first four disks contain 32 volume segments that can be allocated to up to 32
separate Traditional volumes. (4 disks x 1 partition per disk x 8 volume segments per partition = 32
volume segments) You choose to create 8 Traditional volumes, each with 4 segments that span the
four disks.
For data fault tolerance, you create four software RAID1 mirrored partitions on the fifth server disk,
where the other device's partition are mirrored separately. In
smaller disks are mirrored to similarly sized partitions on one larger disk. In this configuration, if
any of the small disks fail, the data on the volume segments can be recovered from the mirrored
partition. However, if the large server disk fails, all of the mirrored partitions would also fail. The
original data would not be harmed.
Mirroring Small Disks to Partitions on One Large Disk
Figure 5-1
Mirrored to
Disk 3
partition 3
Mirrored to
Disk 2
partition 2
Mirrored to
Disk 1
partition 1
Mirrored to
Disk 0
partition 0
5.2 Managing Traditional Software RAID1
Devices
This section discusses the following management tasks:
Section 5.2.1, "Mirroring Partitions," on page 37
Section 5.2.2, "Unmirroring Partitions," on page 38
Section 5.2.3, "Recovering Data from an Out of Sync Disk," on page 38

5.2.1 Mirroring Partitions

You set the Mirror attribute for a partition when you create it.
1 In Novell Remote Manager for NetWare, click Manage Server > Partition Disks.
2 Locate the device that you want to create the partition on, then click Create.
3 In the Partition Type drop-down list, select the type of partition you want to create.
Figure
Disk 4
NetWare
Partition 3
NetWare
Partition 2
NetWare
Partition 1
NetWare
Partition 0
Using Software RAID1 Devices for Data Fault Tolerance
5-1, single partitions on several
37