1. A storage system comprising: a storage array controller; and a first offload environmental service module (ESM) in communication with, and separate from, the storage array controller, the first offload ESM having an input/output controller (IOC) configured as a target device that presents a target for storage drives to the storage array controller, the IOC configured to operatively communicate with the storage array controller, further wherein the IOC is configured to perform at least one function of the storage array controller that has been offloaded from the storage array controller to the first offload ESM; wherein the first offload ESM is in communication with a second offload ESM that is separate from the storage array controller; wherein the first offload ESM includes non-volatile memory, where the first offload ESM is configured to mirror write-back cached data between the first and second offload ESMs, further wherein the first offload ESM provides environmental services monitoring and management functions for the storage system, and wherein, in response to receiving a command to commit the write-back cached data to the storage drives and receiving a status from the storage drives to confirm transferring the write-back cached data from the non-volatile memory to the storage drives has been completed, the first offload ESM marks the write-back cached data as no longer dirty and returns the status to the storage array controller.