Why do multiple mock disks appear on the application server after the log on operation is repeatedly performed?

Publication Date:  2016-11-30 Views:  182 Downloads:  0
Issue Description
Why do multiple mock disks appear on the application server after the log on operation is repeatedly performed?
Solution
Every time when the log on operation is performed on an AS, a session is established between the AS and the storage system. Based on the session, the operating system (OS) of the AS scans the mapped LUNs. If the multipathing software is not installed, the OS cannot determine whether the LUNs scanned from several physical paths are the same LUN, and assumes them as different LUNs (the number of LUNs is equal to the times of performing the log on operation); therefore, multiple mock disks appear on the AS. If the multipathing software is installed, it can determine whether the LUNs in different sessions are the same LUN by analyzing the world wide name (WWN) of each LUN, and eliminates the mock disks.

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