Disclosed is a storage system architecture. An Environmental service module (ESM) is coupled to one or more array controllers. The ESM is configured with a central processing unit and one or more assist functions. The assist functions may include nonvolatile memory. This nonvolatile memory may be used for write caching, mirroring data, and/or configuration data. The assist functions, or the ESM, may be controlled by the array controllers using SCSI or RDMA commands.