Home > Integrated Products > VxBlock 1000 and 3-Tier Platform Reference Architectures > Guides > 3-Tier Platform Design Guide > Cisco UCS fabric interconnects
Every 3-Tier Platform that Cisco Intersight manages is equipped with two Cisco UCS 4th or 5th-generation FIs to form an HA cluster.
The following table shows the supported 3-Tier FI configurations.
Note: You cannot use the Cisco UCS 2408 IOM on a Cisco UCS X9508 chassis, or a Cisco UCS 9108 IFM on a Cisco UCS 5108 chassis.
FI | Chassis |
Cisco 2408 IOM | Cisco UCS 5108 chassis |
Cisco UCS 9108 IFM | Cisco UCS X9508 chassis |
Cisco UCS 2408 IOM requires Cisco UCS Intersight Infrastructure 4.1 (2b) or later.
To run IMM on your FIs, use IMM version 4.1 (3) or later.
Each FI pair performs the following functions on the 3-Tier Platform: