System Architecture Overview - Western Digital Ultrastar Serv60+8 User Manual

User Guide
• Dual Skylake LGA3647 Socket Processors
• 16 DDR4 ECC DIMM slots
• ASPEED AST2500 BMC
• Lewisburg PCH C624 Chipset

1.2 System Architecture Overview

Storage Subsystem Overview
The Ultrastar Serv60+8 IOM uses a cascaded expander design to allow for connection to all 60 HDD drives.
The minimum configuration comes with two of the six PCIe slots pre-populated with a combination of internal
SAS HBAs and RAID adapters that act as an interconnect between the server subsystem and the storage
subsystem by connecting to the system SSDs and the IOM. The exact configuration of the PCIe slots may
vary depending the specific version of the Ultrastar Serv60+8. The eight system SSDs are connected via one
of these SAS HBAs.
The storage subsystem out-of-band management microprocessor provides an Ethernet connection using a
Redfish/RESTful API to access the various enclosure services. All the SES enclosure information can be
obtained through the out-of-band management port. Major use cases for this feature include obtaining storage
subsystem health information, locating enclosure components using the IDENT LEDs, and updating expander
and storage OOBM firmware.
The system FPGAs control and report the states of the four storage subsystem fans, drive LEDs, and T10
drive power disable signals on the 60 HDD data storage drives.
Note: To use T10 power disable, the drives installed must also support this
feature.
2
The I C architecture is designed to support only one single master on any given bus. The primary expander
will be the master on each I
number of devices on each bus are balanced to allow communication to peripheral devices and not overload
any one bus. The devices connected on the I
FPGAs, and SAS connectors among others.
Four of the six total fans are controlled by the storage subsystem. Status and control for these four fans is
handled by the in-band SES management interface called the SEP and the Redfish OOBM.
Server Subsystem Overview
The server subsystem is situated in an individual compartment at the rear of the unit. It is comprised of a dual
socket Intel Sawtooth Pass S2600ST that supports LGA3647 socket Intel Xeon processors. The Ultrastar
Serv60+8 has 16 DDR4 ECC DIMM slots for memory that support a clock speed of 2666 MHz, and it leverages
the Intel C624 chipset. The motherboard also hosts an ASPEED AST2500 BMC for out-of-band management
of the server components. The server motherboard has a total of six PCIe slots that support PCIe 3.0, two
M.2 ports that can host compatible SSDs for the system OS.
2 2
C bus. There are eight I
2
C buses include the enclosure VPDs, temp sensors, baseboard
10
1.2
C buses used in the Ultrastar Serv60+8 enclosure. The
1 Overview
System Architecture Overview