User Guide

The switches are installed in I/O module bays in the rear of the Flex System chassis, as shown in Figure 2.
Switches are normally installed in pairs because ports on the I/O adapter cards installed in the compute nodes
are routed to two I/O bays for redundancy and performance.
Figure 2. Location of the I/O bays in the Flex System chassis
The CN4093 switch can be installed in bays 1, 2, 3, and 4 of the Flex System chassis. A supported adapter
card must be installed in the corresponding slot of the compute node. Each adapter can use up to four lanes to
connect to the respective I/O module bay. The CN4093 is able to use up to three of the four lanes.
Prior to Networking OS 7.8, with four-port adapters, an optional Upgrade 1 (00D5845) or Upgrade 2 (00D5847)
was required for the switch to allow communications on all four ports. With eight-port adapters, both optional
Upgrade 1 (90Y3562) and Upgrade 2 (00D5847) were required for the switch to allow communications on six
adapter ports, and two remaining ports are not used. With Networking OS 7.8 or later, there is no need to buy
additional switch upgrades for 4-port and 8-port adapters if the total number of port licenses on the switch
does not exceed the number of external (upstream network ports) and internal (compute node network ports)
connections used.
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 is not required. However,
when needed, the periscope connector can be replaced with the adapter card. In this case, integrated NIC will
be disabled.
Table 4 shows compatibility information for the CN4093 and Flex System chassis.
Table 4. Flex System chassis compatibility
Description Part
number
Enterprise
Chassis with
CMM
Enterprise
Chassis with
CMM2
Carrier-grade
Chassis with
CMM2
Flex System Fabric CN4093 10Gb Converged Scalable
Switch
00D5823 Yes Yes No
The midplane connections between the adapters installed in the compute nodes to the switch bays in the
chassis are shown diagrammatically in the following figure. The figure shows both half-wide compute nodes,
such as the x240 with two adapters, and full-wide compute nodes, such as the x440 with four adapters.
Flex System Fabric CN4093 10Gb Converged Scalable Switch (withdrawn product) 13