UIM requirements for Shared Disk or VMDK vs RDM in a clustered environment

Products

• DX Unified Infrastructure Management (Nimsoft / UIM)

Issue/Introduction

Infrastructure team wants to migrate existing VMs to a new environment and converting RDM disks to VMDK.   We have some disks on the UIM Database Server which are showing as shared disk.  Is there any requirement for shared disk in UIM DB?  Any issue with VMDK disks instead of RDM?

Environment

DX UIM - Any Version
clustered server for primary hub or database

Resolution

From the perspective of DX UIM itself, there is no requirement for any specific type of VM disk infrastructure, so RDM or VMDK are fine.

There is also no specific requirement within DX UIM for any server to have shared disks.

However, a shared disk may be involved with a cluster - either an active/passive cluster hosting the primary hub, or a Database cluster (e.g. SQL AlwaysOn or Oracle RAC cluster.)

If your server is indeed part of a Microsoft Cluster, Oracle RAC, or another cluster needing shared access, converting a shared RDM to VMDK is not as simple as clicking “convert.” You must ensure that:

• You properly quiesce or remove the disk from active cluster control.
• The new VMDK is configured to allow multi-writer and SCSI bus sharing if you still need it to be shared among multiple VMs.
• You thoroughly test the cluster afterward to confirm no data corruption or loss of functionality.
  
  

These considerations are outside the scope of DX UIM Support.  Always coordinate with both your VMware and Oracle teams (and/or documentation) before making this type of change in a clustered environment.