User manual

INTRODUCTION

1.3.4 Online RAID Level and Stripe Size Migra-

tion

User can migrate both the RAID level and stripe size of an existing

volume set, while the server is online and the volume set is in use.

Online RAID level/stripe size migration can prove helpful during

performance tuning activities as well as in the event that additional

physical disks are added to the SATA RAID controller. For example,

in a system using two drives in RAID level 1, you could add capac-

ity and retain fault tolerance by adding one drive. With the addi-

tion of third disk, you have the option of adding this disk to your

existing RAID logical drive and migrating from RAID level 1 to 5.

The result would be parity fault tolerance and double the available

capacity without taking the system off.

1.4 High availability

1.4.1 Creating Hot Spares

A hot spare drive is an unused online available drive, which is ready

for replacing the failure disk drive. In a RAID level 1, (10), 3, or 5

raid set, any unused online available drive installed but not belong-

ing to a raid set can deﬁne as a hot spare drive. Hot spares permit

you to replace failed drives without powering down the system.

When SATA RAID controller detects a SATA drive failure, the system

will automatic and transparent rebuilds using hot spare drives. The

raid set will be reconﬁgured and rebuilt in the background, while

the SATA RAID controller continues to handle system request. Dur-

ing the automatic rebuild process, system activity will continue as

normal, however, the system performance and fault tolerance will

be affected.

Important:

The hot spare must have at least the

same capacity as the drive it replaces.