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The IBM Flex System™ EN4091 10Gb Ethernet Pass-thru Module offers easy connectivity of the IBM Flex System Enterprise Chassis to any external network infrastructure. This unmanaged device enables direct connectivity of the compute node in the chassis to an external top-of-rack data center switch. This module can function at both 1 Gb and 10 Gb Ethernet speeds. It has fourteen internal 10 Gb links, and fourteen external 10 Gb SFP+ uplinks.
Changes in the December 1 update:
* IBM Flex System CN4052 2-port 10Gb Virtual Fabric Adapter now supported
* IBM Flex System CN4058S 8-port 10Gb Virtual Fabric Adapter now supported
The IBM Flex System™ EN4091 10Gb Ethernet Pass-thru Module offers easy connectivity of the IBM Flex System Enterprise Chassis to any external network infrastructure. This unmanaged device enables direct Ethernet connectivity of the compute node in the chassis to an external top-of-rack data center switch. This module can function at both 1 Gb and 10 Gb Ethernet speeds. It has fourteen internal 1 Gb or 10 Gb links, and fourteen external 1 Gb or 10 Gb SFP+ uplinks.
The following figure shows the IBM Flex System EN4091 10Gb Ethernet Pass-thru Module.
Figure 1. IBM Flex System EN4091 10Gb Ethernet Pass-thru Module
Did you know?
The IBM Flex System EN4091 10Gb Ethernet Pass-thru Module provides 14 internal and 14 external 10 Gb Ethernet ports, and it supports 1 Gb and 10 Gb Ethernet signaling for Converged Enhanced Ethernet (CEE), Fibre Channel over Ethernet (FCoE), and other Ethernet-based transport protocols.
IBM Flex System, a new category of computing and the next generation of Smarter Computing, offers intelligent workload deployment and management for maximum business agility. This chassis delivers high-speed performance complete with integrated servers, storage, and networking for multi-chassis management in data center compute environments. Furthermore, its flexible design can meet the needs of varying workloads with independently scalable IT resource pools for higher utilization and lower cost per workload. While increased security and resiliency protect vital information and promote maximum uptime, the integrated and easy-to-use management system reduces setup time and complexity, providing a quicker path to return on investment (ROI).
Part number information
The IBM Flex System EN4091 10Gb Ethernet Pass-thru Module has 14 internal and 14 external ports that can operate at 1 Gb or 10 Gb Ethernet speeds. The following table shows the part numbers for ordering the Pass-thru Module.
Table 1. Part numbers and feature codes for ordering
|Description||Part number||Feature codes*|
|IBM Flex System EN4091 10Gb Ethernet Pass-thru Module||88Y6043||A1QV / 3700|
The part number for the IBM Flex System EN4091 10Gb Ethernet Pass-thru Module, 88Y6043, includes the following items:
- One IBM Flex System EN4091 10Gb Ethernet Pass-thru Module
- IBM Important Notices flyer and Warranty Flyer
- Documentation CD-ROM
Note: QSFP and SFP+ transceivers or cables are not included with the module.
The IBM Flex System EN4091 10Gb Ethernet Pass-thru Module is particularly suited for the following clients:
- Clients who require direct connectivity of the compute nodes in the chassis to an external TOR data center switch
- Clients who are implementing a converged environment
- Clients who want to reduce total cost of ownership (TCO) and improve performance, while maintaining high levels of availability and security
- Clients who want to avoid oversubscription, which can result in congestion and loss of performance
Features and specifications
The IBM Flex System EN4091 10Gb Ethernet Pass-thru Module has the following features and specifications:
- Internal ports: Fourteen internal full-duplex Ethernet ports that can operate at 1 Gb or 10 Gb speeds.
- External ports: Fourteen ports for 1 Gb or 10 Gb Ethernet SFP+ transceivers (support for 1000BASE-SX, 1000BASE-LX, 1000BASE-T, 10GBASE-SR, or 10GBASE-LR) or SFP+ copper direct-attach cables (DAC). SFP+ modules and DAC cables are not included and must be purchased separately.
- An unmanaged device that has no internal Ethernet management port, but is able to provide its vital product data (VPD) to the secure management network in the Chassis Management Module.
Supported transceivers and cables
The following table lists the supported cables and transceivers.
Table 2. Supported transceivers and DAC cables
|Part number||Feature code*||Description|
|SFP transceivers - 1 GbE|
|81Y1618||3268 / EB29||IBM SFP RJ-45 Transceiver (does not support 10/100 Mbps)|
|00FE333||A5DL / EB29||IBM SFP 1000Base-T (RJ-45) Transceiver (does not support 10/100 Mbps)|
|81Y1622||3269 / EB2A||IBM SFP SX Transceiver|
|90Y9424||A1PN / None||IBM SFP LX Transceiver|
|SFP+ transceivers - 10 GbE|
|46C3447||5053 / EB28||IBM SFP+ SR Transceiver|
|90Y9412||A1PM / ECB9||IBM SFP+ LR Transceiver|
|44W4408||4942 / 3382||10GbE 850 nm Fiber SFP+ Transceiver (SR)|
|SFP+ Direct-attach copper (DAC) cables - 10 GbE|
|81Y8295||A18M / EN01||1m 10GE Twinax Act Copper SFP+|
|81Y8296||A18N / EN02||3m 10GE Twinax Act Copper SFP+|
|81Y8297||A18P / EN03||5m 10GE Twinax Act Copper SFP+|
|95Y0323||A25A / None||1m IBM Active DAC SFP+ Cable|
|95Y0326||A25B / None||3m IBM Active DAC SFP+ Cable|
|95Y0329||A25C / None||5m IBM Active DAC SFP+ Cable|
|90Y9427**||A1PH / None||1m IBM Passive DAC SFP+|
|90Y9430**||A1PJ / None||3m IBM Passive DAC SFP+|
|90Y9433**||A1PK / ECB6||5m IBM Passive DAC SFP+|
** The EN4091 10Gb Pass-Thru supports Passive DAC cables as of firmware 126.96.36.199
With the flexibility of the IBM Flex System EN4091 10Gb Ethernet Pass-thru Module, clients can take advantage of the technologies that they require for multiple environments:
- For 1 GbE links, you can use SFP transceivers plus RJ-45 cables or LC-to-LC fiber cables, depending on the transceiver.
- For 10 GbE, you can use direct-attached copper (DAC, also known as Twinax) cables, which come in lengths between 1 m and 5 m. These DAC cables are a cost-effective and low-power alternative to transceivers, and are ideal for all 10 Gb Ethernet connectivity to the Top-of-the-Rack (TOR) switches. For longer distances, you can use SFP+ transceivers (SR or LR) plus LC-to-LC fiber optic cables.
Supported chassis and adapter cards
The pass-thru modules are installed in I/O bays in the rear of the IBM Flex System Enterprise Chassis, as shown in the following figure. I/O modules are normally installed in pairs because I/O adapter cards installed in the compute nodes route to two I/O bays for redundancy and performance.
Figure 2. Location of the I/O module bays in the IBM Flex System Enterprise Chassis
The connections between the adapters installed in the compute nodes to the switch bays in the chassis are shown in the following figure. The figure shows both half-wide servers, such as the x240 with two adapters, and full-wide servers, such as the x440 with four adapters.
Figure 3. Logical layout of the interconnects between I/O adapters and EN4091 modules
The EN4091 10Gb Ethernet Pass-thru Module can be installed in bays 1, 2, 3, and 4 of the chassis. A supported Ethernet adapter must be installed in the corresponding slot of the compute node (slot A1 when modules are installed in bays 1 and 2 or slot A2 when modules are in bays 3 and 4).
In compute nodes that have an integrated dual-port 10 GbE network interface controller (NIC), NIC ports are routed to bays 1 and 2 with a specialized periscope connector, and the adapter card in slot A1 is not required. However, when needed, the periscope connector can be replaced with the adapter card. In that case, an integrated NIC is disabled.
The following table shows the connections between the adapters installed in the compute nodes to the I/O module bays in the chassis.
4-port and 8-port adapters: With 4-port 1 GbE or 10 GbE or 8-port 10 GbE adapters, only up to two adapter ports can be used with the EN4091 pass-thru modules (one port per pass-thru module).
Table 3. Adapter to I/O bay correspondence
|I/O adapter slot|
in the server
|Port on the adapter||Corresponding I/O module bay in the chassis|
|Bay 1||Bay 2||Bay 3||Bay 4|
|Slot 1||Port 1||Yes|
|Slot 2||Port 1||Yes|
(full-wide compute nodes only)
(full-wide compute nodes only)
The following table lists the compatibility information for the I/O adapters and EN4091 10Gb Ethernet Pass-thru Modules.
Table 4. Network adapters
EN4091 10Gb Ethernet Pass-thru Module
|40 Gb Ethernet|
|EN6132 2-port 40Gb Ethernet Adapter||90Y3482||A3HK||A3HK|
|10 Gb Ethernet|
|Embedded 10Gb Virtual Fabric Adapter in the x240||None||None||None|
|Embedded 10Gb Virtual Fabric Adapter in the x222||None||None||None|
|Embedded 10Gb Virtual Fabric Adapter in the x440||None||None||None|
|IBM Flex System CN4022 2-port 10Gb Converged Adapter||88Y5920||A4K3||A4K3|
|IBM Flex System CN4052 2-port 10Gb Virtual Fabric Adapter||00JY800||A5RP||None|
|IBM Flex System CN4054 10Gb Virtual Fabric Adapter (4-port)||90Y3554||A1R1||1759|
|IBM Flex System CN4054R 10Gb Virtual Fabric Adapter (4-port)||00Y3306||A4K2||A4K2|
|IBM Flex System CN4058 8-port 10Gb Converged Adapter||None||None||EC24|
|IBM Flex System CN4058S 8-port 10Gb Virtual Fabric Adapter||94Y5160||A4R6||None|
|IBM Flex System EN4054 4-port 10Gb Ethernet Adapter||None||None||1762|
|IBM Flex System EN4132 2-port 10Gb Ethernet Adapter||90Y3466||A1QY||EC2D|
|IBM Flex System EN4132 2-port 10Gb RoCE Adapter||None||None||EC26|
|1 Gb Ethernet|
|EN2024 4-port 1Gb Ethernet Adapter||49Y7900||A10Y||1763|
|Embedded 1Gb Ethernet in the x220||None||None||None|
The adapters are installed in slots in each compute node. The following figure shows the locations of the slots in the x240 Compute Node. The positions of the adapters in the other supported servers are similar.
Figure 4. Location of the I/O adapter slots in the IBM Flex System x240 Compute Node
The module supports the following IEEE standards:
- IEEE 802.3ab 1000BASE-T copper twisted pair Gigabit Ethernet
- IEEE 802.3z 1000BASE-SX short range fiber optics Gigabit Ethernet
- IEEE 802.3z 1000BASE-LX long range fiber optics Gigabit Ethernet
- IEEE 802.3ae 10GBASE-SR short range fiber optics 10 Gb Ethernet
- IEEE 802.3ae 10GBASE-LR long range fiber optics 10 Gb Ethernet
- 10GSFP+Cu SFP+ Direct Attach copper
Connectors and LEDs
The following figure shows the front panel of the IBM Flex System EN4091 10Gb Ethernet Pass-thru Module.
Figure 5. Front panel of the IBM Flex System EN4091 10Gb Ethernet Pass-thru Module
The front panel has the following components:
- LEDs that show the status of the module and the network:
- The OK LED indicates that the module has passed the power-on self-test (POST) with no critical faults and is operational.
- The blue Identify LED is used to identify the module physically by using the management software to illuminate it.
- The error LED (pass-thru module error) indicates that the module has failed the POST or detected an operational fault.
- Fourteen external SFP+ ports for 1 Gb or 10 Gb connections to external Ethernet devices.
- An Ethernet link OK LED and an Ethernet Tx/Rx LED for each external port on the module.
Network cabling requirements
The network cables that can be used with the IBM Flex System EN4091 10Gb Ethernet Pass-thru Module are as follows:
- 10GBASE-SR (requires the optional 10 GbE SFP transceivers listed in Table 2)
- 850 nm communication using multimode fiber cable (50 µ or 62.5 µ) up to 300 m, LC duplex connector
- 10GBASE-LR (requires the optional 10 GbE SFP+ transceivers listed in Table 2)
- 1310 nm communication using single-mode fiber cable up to 10 km, LC duplex connector
- 1000BASE-SX (requires the optional 1 GbE SFP transceivers listed in Table 2)
- 850 nm communication using multimode fiber cable (50 µ or 62.5 µ) up to 550 m, LC duplex connector
- 1000BASE-LX (requires the optional 1 GbE SFP transceivers listed in Table 2)
- 1310 nm communication using single-mode fiber cable up to 10 km, LC duplex connector
- 1000BASE-T (requires the optional RJ-45 SFP transceivers)
- UTP Category 6
- UTP Category 5e (100 m maximum)
- UTP Category 5 (100 m maximum)
- EIA/TIA-568B 100-ohm STP (100 m maximum)
- 10GSFP+Cu (requires the optional SFP+ DAC cables listed in Table 2)
- SFP+ copper direct attach cables (which can be up to 5 m) listed in Table 2
There is a 1-year, customer-replaceable unit (CRU) limited warranty. When installed in a chassis, these I/O modules assume your system’s base warranty and any IBM ServicePac® upgrades.
These are the approximate dimensions and weight of the IBM Flex System EN4091 10Gb Ethernet Pass-thru Module:
- Height: 30 mm (1.2 in.)
- Width: 401 mm (15.8 in.)
- Depth: 317 mm (12.5 in.)
- Weight: 3.7 kg (8.1 lb)
Shipping dimensions and weight (approximate):
- Height: 114 mm (4.5 in.)
- Width: 508 mm (20.0 in.)
- Depth: 432 mm (17.0 in.)
- Weight: 4.1 kg (9.1 lb)
The IBM Flex System EN4091 10Gb Ethernet Pass-thru Module conforms to the following standards:
- United States FCC 47 CFR Part 15, Subpart B, ANSI C63.4 (2003), Class A
- IEC/EN 60950-1, Second Edition
- Canada ICES-003, issue 4, Class A
- Japan VCCI, Class A
- Australia/New Zealand AS/NZS CISPR 22:2006, Class A
- Taiwan BSMI CNS13438, Class A
- CE Mark (EN55022 Class A, EN55024, EN61000-3-2, EN61000-3-3)
- CISPR 22, Class A
- China GB 9254-1998
- Turkey Communique 2004/9; Communique 2004/22
- Saudi Arabia EMC.CVG, 28 October 2002
The following figure shows the usage of the IBM Flex System EN4091 10Gb Ethernet Pass-thru Module to route two integrated 10 GbE ports and two 10 GbE ports on the dual-port expansion card installed in slot 2 of the compute node. Each compute node has a total of four 10 GbE ports, and four IBM Flex System EN4091 10Gb Ethernet Pass-thru Module are installed in bays 1, 2, 3, and 4 of the Enterprise Chassis. The connections between the adapter card and the modules are internal to the chassis. No cabling is needed.
Figure 5. Using the IBM Flex System EN4091 10Gb Ethernet Pass-thru Module with integrated 10 GbE NICs and dual-port 10 GbE adapter cards
The following table lists the solution components.
Table 5. Components used when connecting the adapter to the 10Gb Ethernet Pass-thru Modules
|Part number/machine type||Description||Quantity|
|8737-x2x||IBM Flex System x240 Compute Node with Embedded 10Gb Virtual Fabric Adapter||1 to 14|
|90Y3466||IBM Flex System EN4132 2-port 10Gb Ethernet Adapter||1 per server|
|8721-A1x||IBM Flex System Enterprise Chassis||1|
|88Y6043||IBM Flex System EN4091 10Gb Ethernet Pass-thru Module||4|
|Varies||DAC cables or SFP+ modules (See Table 2 for details.)||Up to 14 per pass-thru module (one cable or SFP+ module per server's network port connected to the EN4091 is required)|
For more information, see the following IBM Flex System EN4091 10Gb Ethernet Pass-thru Module product publications, available from the IBM Flex System Information Center:
- Installation and User's Guide
Here are other useful references:
- US Announcement Letter 112-053
- IBM Flex System Enterprise Chassis Product Guide
- IBM Flex System Information Center (User's Guides for servers and options)
- IBM Flex System Interoperability Guide
- IBM Redbooks® publication IBM Flex System Products and Technology, SG24-7984
- IBM Redbooks Product Guides for IBM Flex System servers and options
- IBM Configurator for e-business (e-config)
- IBM System x and Cluster Solutions configurator (x-config)
- IBM System x Configuration and Options Guide:
- ServerProven for IBM Flex System
This material has not been submitted to any formal IBM test and is published AS IS. It has not been the subject of rigorous review. IBM assumes no responsibility for its accuracy or completeness. The use of this information or the implementation of any of these techniques is a client responsibility and depends upon the client's ability to evaluate and integrate them into the client's operational environment.