Oracle Licensing – The vMotion Trap

A recurring theme in Oracle audits recently has been the focus on VMware vCenter Server. vCenter Server is the application used to manage one of more ESXi hosts, which in turn host virtual machines (servers). It also orchestrates how virtual machines (VM) are deployed, the resources they are allowed use, what happens in the event of a cluster going down, etc. It is the control vCenter has, especially when the vMotion feature is enabled that has drawn the attention of the Oracle LMS auditors and the opportunity to extract more revenue.


VMware allows you to turn a physical server (ESXi Host) into many virtual servers. It is well known that Oracle does not recognize VMware’s partitioning method (how you divide up the server resources) and has always insisted that the physical server must be licensed. What is less well-known is that Oracle also insist that if there is more than one physical server (ESXi Hosts) in a cluster then all servers (know as nodes) in the cluster must be fully licensed also, even if Oracle products are only running on one of the nodes in the cluster.

Why vMotion is a risk


VMware comes with a really awesome feature called vMotion which basically allows you to move a virtual machine (VM) from one host to another with little or no effort (DRS Host Affinity rules). This is great for the system administrators as it allows them to manually or automatically move workloads to ensure best performance and gracefully move workloads around when upgrades or maintenance is underway. The vMotion feature should not be confused with the VMware High Availability (HA) cluster which ensures the service keeps going in the event of an unexpected host going down. While most organizations would expect to license Oracle products in a HA configuration they would not expect to license all nodes in a cluster with the vMotion feature enabled or managed by the same vCenter Server. The problem is that Oracle have now started to take a very strict interpretation of what constitutes a cluster with Oracle LMS insisting that all nodes in all clusters managed by a vCenter must be licensed, even if the other clusters do not have Oracle products running on them. The argument is that you could (using vMotion) move a VM to another cluster.

vMotion and Oracle

So what do you do if you have one vCenter managing a number of ESXi hosts? In a perfect world to be compliant you would need to have all your Oracle products on dedicated hosts and clusters with their own dedicated vCenter not linked to any other vCenter. In the real world, you’ll need to demonstrate that you have made all reasonable efforts to ensure license compliance. Some steps that will help:

  • ensure you have clear process and protocols in place, documented and communicated to staff
  • enable and backed-up host-level change-tracking (hostd.log and VMware.log) to prove VM’s have not moved in the past.
  • Use best practice when configuring your vMotion Management Network
  • Use separate management (VLAN ) and vMotion networks for each cluster, now the VM can’t move!

Even with these measures you can expect strong argument from Oracle LMS just push back.


There is no denying that with Oracle’s database sales revenues flat for the last year we can expect strict interpretation of the licensing rules going forward. Couple this with the fact that most VMware customers will have upgraded by now to an edition that includes the full vMotion features and it’s going to be shooting fish in a barrel for Oracle LMS unless customers push back.

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Piaras MacDonnell