The issue is the sg device assigned by system may be locked by unknown reason. The cli communicates to the RAID card through the sg device, so you will get timeout errors on using cli if the sg device is not available. Since sg device is independent of volumes, you can continue to access these arrays without problem. This problem relative kernel version only happens on some kernels. It may decrease the chance of this error by disabling smartd and smartmontool. If your system is installed in another device not the array, you can reset the sg device to be able to bring the sg device back. But arrays will be not available when the sg device is resetting.
Tags: CLI, Linux