Best Practices for the Sun StorEdge 3320 SCSI Array and Sun StorEdge 3310 SCSI Array
5
Direct-Attached Storage
One powerful feature of Sun StorEdge 3000 Family SCSI arrays is their ability to
support multiple direct-attached servers without requiring storage switches. Servers
can be directly connected using built-in external SCSI ports, if available, or add-in
SCSI host-bus adapter cards.
Sun StorEdge 3000 Family SCSI arrays automatically configures ports to match the
transfer speed and communication method of each connection.
The actual number of servers that can be connected depends on the number of SCSI
connections used for each server. Configurations can support:
■
Two servers with redundant connections for Sun StorEdge 3320 SCSI arrays
■
Three servers in non-redundant configurations
Dual-Controller Configurations
Using redundant connections between SCSI arrays and servers provides failover
protection in the event a connection becomes unreliable or fails.
Single-Controller Configurations
Using single connections between SCSI arrays and servers creates single points of
failure (SPOF) that can cause interruptions in the event a connection becomes
unreliable or fails. This is not a recommended configuration unless host-based
mirroring is utilized to protect against single points of failure. Similarly, using only a
single controller creates a single point of failure, unless single controllers are used in
pairs and mirrored. Using a dual-controller configuration is preferable to using a
single controller or a pair of single controllers.
Tips and Techniques
■
A Sun StorEdge 3000 Family SCSI array with a single controller can be configured
to support up to three host connections. These connections can be used in pairs,
individually, or in any combination of both.
■
This single-controller configuration offers no redundancy. Consider mirroring
single controllers or using dual controllers instead to achieve redundancy and
increase reliability, availability, and serviceability. See
“General Configuration
Considerations” on page
7
for more information.
