Azure site recovery by on-premises Windows Hyper-V VMs replication
There are many ways in which we can set up an Azure-based site recovery for Windows servers.
I am explaining the steps as follows involved in setting up Azure site recovery by on-premises Hyper-V VMs replication
1. Recovery Service Vault
Sign in to the Azure portal and create a ‘Recovery Service Vault’ (Inputs are Preferred Name, Subscription Name, Resource Group name, and Location)
2. Prepare Infrastructure
Open the object created. Open ‘Site Recovery’ page and select ‘Prepare Infrastructure’ as below:
Note the selections as above. I am trying to migrate some of the VMs from my on-premises Hyper-V infrastructure to Azure. As the next step, do an evaluation of the deployment infrastructure (Site Recovery performs optimally when sufficient network bandwidth and storage are provisioned. Allocating insufficient capacity can lead to replication issues.). You may refer the following link for more details
Azure Site Recovery Deployment Planner
3. Prepare the Hyper-V source
Now, we are going to prepare the source. On the prepare source page, click the + sign next to ‘Hyper-V Site’, give a preferred name and press OK
Now, the Hyper-V server option will be enabled and click it to add the server. Then the options are shown as below:
In your Hyper-V server, download and install the installer for the site recovery (link shown in the same window. Also, download the vault registration key from the page. So, once the source is ready, you can see the prepare source page as below:
Note: I have stroked out the name of the site in the below image. You can see the name also on this page.
4. Prepare Target:
In target preparation step, you need to create a storage account and Network. If the two resources are already available in your Azure infrastructure, the page will show as below. You may create your own from the page too.
Note: Make sure that you are creating a Resource Manager storage and Network (Not the classic one). Otherwise, you will end up with connectivity issues between storage and network.
5. Create and Associate a Replication Policy
This is the final step of your infrastructure preparation.
Enter the policy name as preferred. In RPO threshold, use the default of 60 minutes. This value defines how often recovery points are created. In Recovery point retention, specify how long each recovery point is retained. Replicated VMs can be recovered to any point in a retention window. In App-consistent snapshot frequency, specify how often app-consistent snapshots are created.
6. Replicate Application
** **Now we are ready to replicate the VMs to Azure. Go to Site Recovery->Step1: Replicate Application. Source, Target, are already set up and proceed to the Virtual Machines page as below:
There were 6 VMs contained in my Hyper-V infrastructure (Names are stroked out). Select the desired VM to be replicated from the list
Configure Properties of the VM selected: Make sure that you follow this step carefully. In this page, basically, you are going to select the disks to be migrated. OS disk should be selected carefully after referring the exact disk at your Hyper-V VM.
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In Replication settings > Configure replication settings, verify that the correct replication policy is selected. Select Enable Replication to start the replication. You can track the progress of the Enable Protection job in Settings > Jobs > Site Recovery Jobs. After the Finalize Protection job runs, the machine is ready for failover. It can take 15 minutes or longer for changes to take effect and appear in the portal.
To monitor VMs you add, check the last discovered time for VMs in Configuration Servers > Last Contact At. To add VMs without waiting for the scheduled discovery, highlight the configuration server (don’t select it) and select Refresh. You can see the status similar to the below image
7. Test Failover
Once the replication status turned to healthy, you can try a Test Failover by selecting 'Test Failover' option as below:
Test Failover creates the VM in your Azure infrastructure
Test Failover options can be selected from the below window: In this page, Select the recovery point. You will need to select an appropriate network Azure prefer a new network than the one which we used for the replication.
Track failover progress on the Jobs tab. You should be able to see the test replica machine in the Azure portal. Usually with the name as Test-yourvmname.
To initiate an RDP connection to the Azure VM, add a public IP to the network interface of the failed over VM.
Once the VM is up and running, make sure that all the disks are online. If not, go to the disk manager and change the disk status from ‘offline’ to ‘online’ to see all your disks in the VM. When everything is working as expected, click Cleanup test failover. This deletes the VMs that were created during test failover.
8. Run a Failover
see [Site Recovery failover at docs.microsft.com]
Once the VM is up and running, make sure that all the disks are online. If not, go to the disk manager and change the disk status from ‘offline’ to ‘online’ to see all your disks in the VM.