Anti-affinity groups specify that specific virtual machines should never run on the same Oracle VM Server. An anti-affinity group applies to all the Oracle VM Servers in a server pool. You may want to set up anti-affinity groups when you want to build-in redundancy or load balancing of specific applications in your environment.

If you add a virtual machine to an anti-affinity group that already has a virtual machine in the group running on the same Oracle VM Server, the job is aborted and the virtual machine is not added to the group. To add the virtual machine to the anti-affinity group, migrate it to another Oracle VM Server, then add it to the group.

If you have set the inbound migration lock feature to disallow new virtual machines on an Oracle VM Server, then any anti-affinity groups you set are restricted from migrating virtual machines, or creating new ones on the server. See Section 7.11, “How Can I Protect Virtual Machines?” for more information on using the inbound migration lock feature.

Details on creating, editing and deleting anti-affinity groups is available in Anti-Affinity Groups Perspective in the Oracle VM Manager User's Guide.