Dell PowerVault 221S (SCSI) - Manual (Page 6)

A REFERENCE GUIDE FOR OPTIMIZING DELL™ SCSI SOLUTIONS VER A02
PAGE 6 11/17/2005
RAID 5
RAID 5 has good I/O performance, data protection and relative cost with excellent storage
capacity. RAID 5 should be used in situations where maximum storage capacity is
required along with a moderate amount of data protection.
RAID 50
A balance between RAID 5 and RAID 10, this solution offers good I/O performance,
availability and good storage capacity. This configuration offers slightly higher
performance than RAID 5, but at a slightly higher cost and reduced storage capacity. It
does however provide greater storage capacity than a RAID 10 solution with a decrease in
performance and data protection. This should be used in situations where greater
redundancy and data protection is required as well as reasonable storage capacity.
Note: For more details on RAID configurations refer to the Dell™ ‘Getting Started with
RAID’ document (
http://support.dell.com/support/edocs/storage/RAID/RAIDbk0.pdf ).
Concatenated Container
This solution is not recommended due to lack of data protection and redundancy and no
performance gain. However for non-critical implementations that require high scalability
this type of solution will provide more ease of use than other RAID configurations.
Application specific guidelines
E-Mail Servers
The storage requirements for e-mail servers can vary depending on the size, the amount,
and type of users. While small departmental e-mail servers may work well with a small
amount of storage and limited features; large corporate e-mail servers normally require
greater storage capacity, very high availability, performance and scalability. IO profiles will
vary depending on the number of users and type of mail and attachments sent.
• Table 2-3: Email Server General I/O profile
I/O Profile
(Read/Write)
I/O Profile
(Sequential/Random)
Bandwidth
I/O
Size
Latency
Sensitivity
Growth
Rate
Critical
ity
60/40 Random Heavy 4k High High High
• Table 2-4: Email Sever RAID Guidelines
RAID Level
Application
Concatenated 0 1 10 5 50
E-Mail
Recommended Not Recommended Possible
Recommended: