Recovery mechanism for I/O module using out-of-band control path

摘要

A storage system includes a storage server and a storage subsystem having an I/O module coupled to disks. The storage server includes a storage adapter coupled to the I/O module creating an in-band (data) path to access data stored on the disks. The storage server sends a data command through the in-band path to the I/O module for accessing the data stored on the disks. The storage server further includes a network adapter coupled to the I/O module creating an out-of-band control path to control the I/O module. The storage server detects through the in-band path that the I/O module is non-responsive to a data command and automatically changes the behavior of the I/O module (e.g., resets the I/O module) through the out-of-band control path to recover the non-responsive I/O module. The storage server also collects and outputs status data of the I/O module through the out-of-band control path.