Knowledge Base

Symptom:

After mapping a LUN to a Windows host server, two identical drives appear instead of one.

Diagnosis:

This issue occurs because Multipath I/O (MPIO) is not configured. Without MPIO, the Windows server detects each path to the LUN as a separate disk, leading to the display of duplicate drives.

Procedure:

• Install MPIO:
  1. Open Server Manager.
  2. Navigate to Add Roles and Features.
  3. Find and install Multipath I/O (MPIO).
• Identify Mapped Disk:
  1. Open Device Manager.
  2. Locate the mapped disk to identify the device Vendor/Device name.
  3. Note the Vendor name (e.g., "IFT") and the Device name (e.g., "GS 3000 SCSI Disk").
• Add MPIO Device:
  1. Open MPIO settings.
  2. The MPIO device name in Microsoft Windows should follow the format: Vendor (8 characters) and Product (16 characters).
  3. Click Add.
  4. Input the device name in the format "IFT GS 3000 Series" in the dialog.
  5. Click OK to close.
• Verify Configuration:
  1. Check that the disk name now shows as “Multi-Path Disk,” indicating MPIO is configured.
  2. Test by failing one connection or controller and verify if there is any impact on running I/O.

By following these steps, you can configure MPIO on your Windows server to properly recognize and handle the mapped LUN, ensuring only one drive is displayed.