Hitachi G1500 - Separated Racks in a Dual Controller Configuration

Although not shown in the following gure, the conguration can include an R2 r
ack
dir
ectly connected to, or separ
ated fr
om the R1 rack. Similarly, the conguration can
include an L2 rack directly connected to, or separated from the L1 rack. To avoid I/O
latency issues, the sum of the length of all cables (controller-to-drive chassis cable and
drive chassis-to-drive chassis cables) cannot exceed 125 meters.
Figure 36 Example of a separated controller and drive-only rack conguration
Separated racks in a dual controller conguration
A dual controller conguration contains two contr
ollers installed into a single rack. The
dual controller conguration can include up to two ash memory drive chassis in the
same rack and separate racks containing only drive chassis.
The following gure shows a dual controller conguration with extended SAS optical
cables connecting between rack R0 (containing both primary and secondary controllers)
and rack R1 (containing two drive chassis) and rack L0 (containing three drive chassis). To
avoid any I/O latency issues the sum of the length of all cables (controller-to-drive
chassis cable and drive chassis-to-drive chassis cable) cannot exceed 125 meters.
Extended cable connections
Chapter 5: Cable connection guidelines
Hitachi Virtual Storage Platform G1000, G1500, and VSP F1500 Hardware Guide 117