Data and Interface Modules

The hardware of the Interface Modules and the Data Modules is a Xyratex 1235E-X1. The module is 87.9 mm (3.46 inches) (2U) tall, 483 mm (19 inches) wide, and 707 mm

(27.8 inches) deep. The weight depends on configuration and type (Data Module or Interface Module) and is a maximum of 30 kg (66.14 lbs). Figure 3-7 on page 51 shows a

representation of a module in perspective.

ATS #1 UPS 3U #2 UPS 3U #3 UPS 3U 30A rated 30A rated 30A Service 30A Service 30A rated 30A Service 30A Service Pigtail

Figure 3-7 Data Module/Interface Module

Data Module

The fully populated rack hosts nine Data Modules (Module 1-3 and Module 10-15). There is no difference in the hardware between Data Modules and Interface Modules (refer to “Interface Module” on page 54) except for the additional host adapters and GigE adapters in the Interface Modules. The main components of the module that are shown in Figure 3-7 in addition to the 12 disk drives are:

򐂰 System planar 򐂰 Processor 򐂰 Memory/cache

򐂰 Enclosure Management Card 򐂰 Cooling devices (fans) 򐂰 Memory Flash Card 򐂰 Redundant power supplies

In addition, each Data Module contains four redundant Gigabit Ethernet ports. These ports together with the two switches form the internal network, which is the communication path for data and metadata between all modules. One Dual GigE adapter is integrated in the System Planar (port 1 and 2). The remaining two ports (3 and 4) are on an additional Dual GigE adapter installed in a PCIe slot as seen in Figure 3-8 on page 52.

Figure 3-8 Data Module connections

System planar

The system planar used in the Data Modules and the Interface Modules is a standard ATX board from Intel®. This high-performance server board with a built-in serial-attached SCSI (SAS) adapter supports:

򐂰 64-bit quad-core Intel Xeon® processor to improve performance and headroom and to provide scalability and system redundancy with multiple virtual applications

򐂰 Eight fully buffered 533/667 MHz dual inline memory modules (DIMMs) to increase capacity and performance

򐂰 Dual Gb Ethernet with Intel I/O Acceleration Technology to improve application and network responsiveness by moving data to and from applications faster

򐂰 Four PCI Express slots to provide the I/O bandwidth needed by servers 򐂰 SAS adapter

Processor

The processor is a XeonQuad Core Processor. This 64-bit processor has the following characteristics:

򐂰 2.33 GHz clock 򐂰 12 MB cache

򐂰 1.33 GHz Front Serial Bus

Memory/Cache

Every module has 8 GB of memory installed (8 x 1 GB FBDIMM). Fully Buffered DIMM memory technology increases reliability, speed, and density of memory for use with Xeon Quad Core Processor platforms. This processor memory configuration can provide three times higher memory throughput, enable increased capacity and speed to balance

Module Power Two different UPS Management USB to Serial 2 x On-board GigE Serial 4 x USB Dual-port GigE Switch N1 Switch N2 Data Module

capabilities of quad core processors, perform reads and writes simultaneously, and eliminate the previous read to write blocking latency.

Part of the memory is used as module system memory, while the rest is used as cache memory for caching data previously read, pre-fetching of data from disk, and for delayed destaging of previously written data. For a description of the cache algorithm, refer to “Write cache protection” on page 36.

Cooling devices

To provide enough cooling for the disks, processor, and board, the system includes 10 fans located between the disk drives and the board. The cool air is aspirated from the front of the module through the disk drives. An air duct leads the air around the processor before it leaves the module through the back. The air flow and the alignment of the fans assure proper cooling of the entire module, even if a fan is failing.

Enclosure management card

The enclosure management card is located between the disk drives and the system planar. In addition to the internal module connectivity between the drive backplane and the system planar, this card is the backplane for the 10 fans. Furthermore, it includes fan control and the logic to generate hardware alarms in the case of problems in the module.

Compact Flash Card

Each module contains a Compact Flash Card (1 GB) in the right-most rear slot. Refer to Figure 3-9.

Figure 3-9 Compact Flash Card

This card is the boot device of the module and contains the software and module configuration files.

Power supplies

Figure 3-10 on page 54 shows the redundant power supplies.

Important: Due to the configuration files, the Compact Flash Card is not interchangeable

Figure 3-10 Redundant module power supplies

The modules are powered by an Astec redundant Power Supply Unit (PSU) cage with a dual 850W PSU assembly as seen in Figure 3-10. These power supplies are redundant and can be individually replaced. Consequently, a power supply failure will not cause an outage, and also, there is no need to stop the system to replace it. The power supply is a field-replaceable unit (FRU).

Interface Module

Figure 3-11shows an Interface Module with iSCSI ports.

Figure 3-11 Interface Module with iSCSI ports

Module Power Two different UPS Management USB to Serial 2 x On-board GigE Serial 4 x USB Quad-port GigE Switch N1 Switch N2 Fibre ports to Patch Panel iSCSI ports to Patch Panel Interface Module with iSCSI ports

The Interface Module is similar to the Data Module. The only differences are:

򐂰 Each Interface Module contains iSCSI and Fibre Channel ports, through which hosts can attach to the XIV Storage System. These ports can also be used to establish Remote Mirror links with another remote XIV Storage System.

򐂰 There are two 4-port GigE PCIe adapters installed for additional internal network connections and also for the iSCSI ports. Refer to Figure 3-11 on page 54 and Figure 3-12.

Figure 3-12 Interface Module without iSCSI ports

All Fibre Channel ports, iSCSI ports, and Ethernet ports used for external connections are internally connected to a patch panel where the external cables are actually hooked up. Refer to 3.2.4, “The patch panel” on page 59.

There are six Interface Modules (modules 4-9) available in the rack.

Fibre Channel connectivity

There are four Fibre Channel (FC) ports (two 2-port adapters) available in each Interface Module for a total of 24 Fibre Channel Protocol (FCP) ports. They support 4Gbps (Gigabit per second) full-duplex data transfer over short wave fibre links, using 50 micron multi-mode cable. The cable needs to be terminated on one end by a Lucent Connector (LC). In each module, the ports are allocated in the following manner:

򐂰 Ports 1 and 2 are allocated for host connectivity 򐂰 Ports 3 and 4 are allocated for remote connectivity

4Gb FC PCI Express adapter

Fibre channel connections to the Interface Modules are realized by two 2-port 4Gb FC PCI

Module Power Two different UPS Management USB to Serial 2 x On-board GigE Serial 4 x USB Quad-port GigE Switch N1 Switch N2 Fibre ports To Patch Panel Management UPS Technician VPN Interface Module without iSCSI ports

Figure 3-13 FC PCI Express Host Adapter

This Fibre Channel host bus adapter (HBA) is LSI’s powerful FC949E controller and features full-duplex capable FC ports that automatically detect connection speed and can

independently operate at 1Gbps, 2Gbps, or 4Gbps. The ability to operate on slower speeds ensures that these adapters remain fully compatible with existing equipment. This adapter also supports new end-to-end error detection through a cyclic redundancy check (CRC) for improved data integrity during reads and writes.

iSCSI connectivity

There are six iSCSI service ports (two ports per Interface Module) available for iSCSI over IP/Ethernet services. These ports are available in Interface Modules 7, 8, and 9 supporting the 1Gbps Ethernet host connection (refer to Figure 3-12 on page 55). These ports need to connect through the patch panel to the user’s IP network and provide connectivity to the iSCSI hosts.

You can operate iSCSI connections for various functionalities:

򐂰 As an iSCSI target that the server hosts through the iSCSI protocol

򐂰 As an iSCSI initiator for Remote Mirroring when connected to another iSCSI port 򐂰 As an iSCSI for data migration when connected to a third-party iSCSI storage system 򐂰 For XCLI and GUI access over the iSCSI ports

iSCSI ports can be defined for various uses:

򐂰 Each iSCSI port can be defined as an IP interface.

򐂰 Groups of Ethernet iSCSI ports on the same module can be defined as a single link aggregation group (IEEE standard: 802.3ad):

– Ports defined as a link aggregation group must be connected to the same Ethernet switch, and a parallel link aggregation group must be defined on that Ethernet switch. – Although a single port is defined as a link aggregation group of one, IBM XIV support

can override this configuration if this setup cannot operate with the client’s Ethernet switches.

򐂰 For each iSCSI IP interface, you can define these configuration options: – IP address (mandatory)

– Network mask (mandatory) – Default gateway (optional)