Consider the following scenario:
- In Windows Server 2012 or Windows Server 2008 R2, you use an Asymmetric Logical Unit Access (ALUA)–capable storage array.
- You configure the array so that every path that's presented to a logical unit number (LUN) has a status of Standby, and the paths cannot be made Active.
When all paths to a LUN are presented as Standby, Windows sends I/O on a path in a non-failed state. If the array responds to this I/O with a "Not Ready" error (such as sense data 0x02/0x04/0x0B [key/code/qualifier]), the system will retry the I/O repeatedly while Windows tries to make a Standby path an Active path.
To work around this issue, do not configure your array in such a way that all paths to a LUN are Standby and no path can be made Active. Because of this failed I/O, you must disconnect the LUNs until the issue is corrected to avoid failures during startup and shutdown.