Introduction 1-1
1.1. Product Overview
This hardware manual briefly introduces the Galaxy GHDX2-2430S/R-16F4D Fibre-4G
to SATA-II RAID subsystem as shown in Figure 1-1.
Figure 1-1: GHDX2-2430S/R-24F4D FC-to-SATA RAID Subsystem
The GHDX2-2430S-24F4D RAID subsystem is powered by a single RAID controller,
the GHDX2-2430R-24F4D by dual redundant RAID controllers. Each RAID controller
comes with two (2) 4Gbps Fibre host channels that are interfaced through four (4)
separate SFP ports. A total of eight (8) SFP ports are available in a redundant-controller
configuration. The additional SFP ports facilitate connection to multiple application
servers and for connecting fault-tolerant data paths. The subsystem houses twenty-four
(24) 3Gbps SATA-II disk drives each with dedicated channel bandwidth. Each controller
board comes with a pre-installed 512MB DDR RAM DIMM module and can support
memory modules with the capacities up to 2GB.
The Galaxy HDX2 series is built around a custom ASIC400 specifically designed with
the hardware RAID6 capability. RAID6 can sustain two member drives of a RAID array
to fail at the same time and thereby helps achieve a higher level of data availability.
There are six (6) dedicated RCC paths strung between the partner RAID controllers in a
dual-active configuration. The RCC chips reside on the third, separate PCI-X bus. This
design takes benefits of the abundant system bandwidth brought by the new architecture
and hence the inter-controller communications do not affect drive channel throughput.