Understanding Fabric Hardware Architecture
The fabric hardware is made up of Fabric Access Processor (FAP) devices on the MIO/DPC/DPC2 cards, and Forwarding Engine (FE) devices on the Fabric and Storage Cards (FCS). Each FAP has three Serializer/Deserializer (SERDES) links to each FE device.
A separate process named ARES Fabric IO (AFIO) configures and manages each individual fabric device. The AFIO process is a standalone executable and not a boxer proclet. This is primarily because the Control plane must be initialized and configured before Boxer is started. The FE devices are managed by AFIO processes running on the Active MIO, one for each FE device. This is because the AFIO process or processes, which run on the local CPU of the MIO/DPC/DPC2 card and the FSC cards do not have a local CPU.
Within Boxer, running on the CPU of the Active MIO, there is a fabric-related controlling proclet named Ares Fabric Controller (AFCtrl). Also within Boxer, on the CPU on each card, there is a process named Ares Fabric Manager (AFMgr). Each AFMgr has an IPC connection to all AFIO processes on the same CPU.
All CLI requests are sent to the AFCtrl proclet on the Active MIO. Depending on the command, AFCtrl forwards the request to one or more AFMgr(s). AFMgr in turn forwards the request to one or more appropriate afios. The AFIO process receives and processes the request, then sends a reply to AFMgr. AFMgr coordinates the individual afio responses by aggregating them into a single reply, which is then sent to AFCtrl. AFCtrl waits for all AFMgr responses, and displays the results.