Dell PowerVault MD3000 - Manual (Page 14)

14
About Your System
RAID Controller Modules
The RAID controller modules provide high-performance, advanced virtual disk configuration, and fault-
tolerant disk subsystem management. Each RAID controller module contains 512 MB of cache that is
mirrored with the other controller's cache for high availability and protected by a battery for up to
72 hours.
Each RAID controller module provides data path and enclosure management functions for your
enclosure, including:
• Monitoring and controlling enclosure environment elements (temperature, fans, power supplies, and
enclosure LEDs)
• Controlling access to the physical disks
• Communicating enclosure attributes and states to the host server
NOTE:
Two RAID controller modules must be installed in the enclosure; a configuration with fewer than two
RAID controller modules installed is not supported.
Depending on which model you choose, the RAID controller module has either single or dual ports for
host access. Various configurations can be utilized to connect the storage enclosure to hosts, depending
on specific redundancy needs. For example:
• Single-port controller - Both RAID controller modules contain a single SAS host port. With a single-
port model, you can connect either:
– A single host with redundant data paths to each RAID controller module
– Two hosts with a single, nonredundant data path to one RAID controller module
• Dual-port controller - Both RAID controller modules contain two SAS host ports. A dual-port model
can connect either:
– One or two hosts with redundant data paths to each RAID controller module
– Up to four hosts with a single, nonredundant data path between each host to one RAID controller
module
For detailed information on cabling, see "Cabling Your RAID Enclosure" on page 21.
RAID Controller Module Connectors and Features
Figure 1-5 shows a single RAID controller module as it appears from the rear of the enclosure. RAID
controller module connectors and components shown include:
• Up to two SAS In port connectors (second SAS In port is optional)
• Ethernet connector
NOTE:
The RAID controller module network configuration can be assigned using a DHCP server (the default
setting). If a DHCP server is not available (time-out is 10 seconds) then the RAID controller modules uses the
static IP addresses of 192.168.128.101 for controller 0 and 192.168.128.102 for controller 1.
• Nine LEDs (three SAS link, two Ethernet link/speed, Battery Fault, Cache Active, Controller Fault,
and Controller Power)