Arista DCS-7816R3-FM | 7800R3 Fabric Module for 7816 Chassis, Slots 1-12

Q: How many DCS-7816R3-FM modules are required for a DCS-7816 chassis?
A: The DCS-7816 chassis requires 12 fabric modules to populate slots 1-12 for full system operation and redundancy. The system supports graceful degradation if fewer modules are installed, though performance may be reduced.

Q: Is the DCS-7816R3-FM compatible with other 7800 Series chassis?
A: No, the DCS-7816R3-FM is specifically designed for the DCS-7816 chassis. Other 7800R3 chassis models (7804, 7808, 7812, 7816L) require their respective fabric modules with different part numbers.

Q: What is the role of fabric modules in the 7800R3 architecture?
A: Fabric modules provide the high-speed interconnect between line cards in the modular chassis, enabling wire-speed forwarding and scalability. They insert from the rear of the chassis and connect directly to line cards via a midplane-less design for maximum performance.

Q: Can I mix R3 and R4 fabric modules in the same chassis?
A: Existing 7800R3 systems can be upgraded to 7800R4 specification with R4 fabric modules and line cards. However, mixing R3 and R4 modules in the same chassis during operation is not recommended; consult Arista documentation for migration procedures.

Q: What software does the fabric module run?
A: Fabric modules operate under the control of the supervisor module, which runs Arista Extensible Operating System (EOS). The supervisor handles all control plane and management functions while fabric modules provide data plane connectivity.