Manage VM high availability

Introduction to VM high availability with layers

In private cloud, to create VMs that will always deploy on separate hypervisor hosts, use anti-affinity layers in your virtual appliance. Each VM in a layer will deploy on a different vCenter host.

Abiquo does not support layers that intersect with other layers. For example, if you have two layers, a VM in the second layer may deploy on the same physical machine as a VM in the first layer.

Ideally, you should design and implement your layers before you deploy your VMs.

Create VMs in anti-affinity layers for high availability

See Create a VM layer

Modify a virtual appliance with anti-affinity layers

You can only make changes to layers that will not compromise anti-affinity while your VMs are deployed or running.

To rename a layer, if the VMs are not deployed, which means they are in the NOT_ALLOCATED state in new in a virtual appliance that is deployed or they are in a virtual appliance that has been undeployed.:

1. Next to the layer name, click the pencil edit button. 

2. Enter the new layer name

To rename a layer, if the VMs are deployed:

1. Create a new layer with the correct name

2. Power off your VMs and move them to the new layer.

To remove a VM that is not deployed from an anti-affinity layer, drag the machine outside the layer and into the general VM area.

To remove one or more deployed VMs from a layer:

1. Power off the VMs

   • You do not have to wait for each one to finish shutting down before moving to the next one

2. Drag each VM out of the layer into the general VM area or into another layer. Note that if they new layer will break the anti-affinity rules, you may not be able to power the VMs on again

To delete a layer:

1. Undeploy all the VMs, which will delete the layer in vCenter, although it will still display in the platform

OR

2. Power off all the VMs and move them out of the layer to the general VM area, which will delete the layer in vCenter

Moving VMs between layers

You can move powered off VMs to a new layer with no existing VMs.

In some environments, you may be able to move a powered off VM to layer with existing deployed VMs. But if you will break the anti-affinity rules of the of the layer by adding the VM, then you will not be able to power on the VM.

You cannot move a VM in a locked state (when it is deploying, reconfiguring, or undeploying).

Manage layers with the API

Note that a layer is an attribute of a VM in the Abiquo database. In the API, Abiquo doesn’t identify the layers with IDs, it uses the layer name in the virtual appliance, for example: /cloud/virtualdatacenters/x/virtualappliances/x/layers/layername