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You can use availability sets to ensure high availability for your VMs in Azure. Each VM in the availability set will deploy on separate, isolated hardware, in a cluster. This is similar to the platform's concept of anti-affinity layers in private cloud. To attach Azure VMs to a basic load balancer, you must add them to the same Availability set. All of the VMs in an Availability set must be in the same Azure Virtual Network, which means they must be in the same virtual datacenter but they can belong to different Resource groups.
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