The supervisor modules for the 7500 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 e?cient 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 monitoring tools.