Abiquo 5.0 introduces support for Availability Sets in Azure to enable users to separate workloads for high availability. All of the VMs in an availability set must be in the same Azure Virtual Network, which means they must be in the same Abiquo virtual datacenter. To add a group of VMs to an Azure load balancer, you must have all the VMs to the same availability set.
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Azure documentation (see reference below) explains fault domains and update domain attributes as follows:
An update domain is a group of VMs and underlying physical hardware that can be rebooted at the same time.
VMs in the same fault domain share common storage as well as a common power source and network switch. After a user creates an Availaiblity set, they can select it when they are create a VM, as for private cloud layers.
When you create a VM, you can select an Availability set. This is similar to the VM layers feature in private cloud.
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