The supervisor modules for the 7300 series run Arista Extensible Operating System (EOS) and handle all control plane and management functions of the system. One supervisor module is needed to run the system and a second can be added for stateful 1+1 redundancy. Each supervisor module takes up only a half slot resulting in very efficient use of space and a higher density design. The quad-core x86 CPU with 16GB of DRAM and an optional SSD provides the control plane performance needed to run an advanced data center switch scaling to over 1,000 physical ports and thousands of virtual ports. A pulse per second clock input port enables synchronizing with an external source to improve the accuracy of network timing and monitoring tools. 

At the heart of the 7300 series is the fabric. It interconnects all line cards in a non-blocking architecture irrespective of the traffic pattern providing a full 2.56 Tbps of forwarding to each line card module. Each line card module connects to the fabric with multiple links and flows are spread across these paths to efficiently utilize the available fabric capacity. The fabric modules are always active-active, providing high availability and can be hot-swapped with graceful performance degradation.

The fabric modules for the two chassis are different based on the size of the chassis and each accommodate a set of individual hot-swap fan modules. The fan modules support forward and reverse airflow and provide redundant cooling. Each fan module can be independently replaced without any impact of the system.