Converting a virtual disk into a Raw Device Mapping

Products

• VMware vSphere ESXi

Issue/Introduction

This article provides the command to convert a virtual disk into a Raw Device Mapping (RDM) in an ESXi/ESX environment.

Environment

VMware ESXi 6.x

VMware ESXi 7.x

VMware ESXi 8.x

Resolution

 

To import a virtual disk into a raw LUN for use with an RDM in ESXi/ESX 6.x and ESXi 7.x/8.0:

1. Log into the ESX host as root via the console or an SSH session
2. Run the command:
   
   # esxcfg-mpath -L
   
   The output appears similar to:
   
   vmhba33:C0:T0:L0 state:active naa.6090a038f0cd6e5165a344460000909b vmhba33 0 0 0 NMP active san iqn.1998-01.com.vmware:bs-tse-i137-35c1bf18 00023d000001,iqn.2001-05.com.equallogic:0-8a0906-516ecdf03-9b9000004644a365-bs-lab-vc40,t,1
   
   
3. Make note of the LUN number (highlighted in red) and the identifier (highlighted in blue).
   
   Note: The disk identifiers may vary depending on the platform or tool you are using. For more information, see kb: https://knowledge.broadcom.com/external/article/316540/identifying-disks-when-working-with-vmwa.html
   
   
4. Run the appropriate command for either the virtual or physical compatibility mode:
   
   
• For virtual compatibility mode, run the command:
  
  # vmkfstools –i srcfile -d rdm:/vmfs/devices/disks/identifier /vmfs/volumes/datastore/vmdir/vmname.vmdk
  
  Note: The identifier value represents the value recorded in step 3.
  
  For example:
  
  # vmkfstools -i olddisk.vmdk -d rdm:/vmfs/devices/disks/naa.0600034392874872788777273 /vmfs/volumes/TestDatastore/TestVM/rdmdisk.vmdk
  
  
• For physical compatibility mode, run the command:
  
  # vmkfstools –i srcfile -d rdmp:/vmfs/devices/disks/identifier /vmfs/volumes/datastore/vmdir/vmname.vmdk
  
  Note: The identifier value represents the value recorded in step 3.
  
  For example:
  
  # vmkfstools -i olddisk.vmdk -d rdmp:/vmfs/devices/disks/naa.0600034392874872788777273 /vmfs/volumes/TestDatastore/TestVM/rdmdisk.vmdk