A path failover occurs when the active path to a LUN is changed from one path to another. Typically, the path failover occurs as a result of a SAN component failure along the current path.
When a path fails, storage I/O might pause for 30-60 seconds until your host determines that the link is unavailable and performs the failover. If you attempt to display the host, its storage devices, or its adapters, the operation might appear to stall. Virtual machines with their disks installed on the SAN can appear unresponsive. After the failover, I/O resumes normally and the virtual machines continue to run.
A Windows virtual machine might interrupt the I/O and eventually fail when failovers take too long. To avoid the failure, set the disk timeout value for the Windows virtual machine to at least 60 seconds.