Are you dreaming of data lose? Are you confident that your Azure disaster recovery plan is robust? 

In this article I am going to talk about implementing Disaster Recovery plan with Azure Site Recovery.

What is Azure Site Recovery?

• Azure Site Recovery is also known as Disaster Recovery as a Service Solution for Azure Vritual Machines, hybrid cloud and related workloads. Once you set up ASR maintains an up-to-date copy of your data in a seperate Azure Region or Availability Zone. Azure Site Recovery continuously replicates the data from one site to another in almost real-time to maintain current copy of your data in a seperate data center. During the disastrous moment on your primary site, Azure Site Recovery lets you fail over to the secondary site.
• Azure Site Recovery comes with many failover options to help with your Recovery Time Object (RTO) and Recovery Point Objececives (RPO).
• Within your Azure Site Recovery plan you can always create recovery groups to define any resource dependencies such as an application server that depends on a database backend or a worker machine, for example.
• Azure Site Recovery plan defines how you failover your resources and how you fail them back to the primary site.

Azure Service Recovery Vault

• Azure Service Recovery Vault contains the settings about how the replication will occur. It also monitors the replication process.
• Make sure you create the Vault in the secondary region to ensure you don't lose it with your other resources of the primary region.
• Before you start the implementation steps, please provision one Windows Virtual Machine in West US 2 region. This Virtual Machine we are going to back up using Azure Site Recovery in the service vault in East US region.

(1) Go to Azure Portal --> Service Recovery Vault

(2) Create a new Service Recovery Vault

(3) Once, the deployment is complete, go to the Vault.Click on Enable Site Recovery.

(4) Now,click on Enable Replication under Azure Virtual Machines

(5)  Now, select the source you want to replicate.

(6) Select the Virtual Machine(s).

(7) Choose the region to back up to. Here, we are selecting East US.

By default, Azure Site Recovery will replicate the source resource group. If you'd like to change how it replicates resources in the group, you may do so by clicking on Customize.

(8)  If you scroll down the page,you will see the Replication Policy. By default, it is called 24-hour-retention-policy.

Here, Recovery Point Rentetion is tha maximum time Azure Site Recovery keeps recovery points. A recovery point is a snapshot of when your data was recoverable, In this example, the recovery point is set 1 day by Azure Site Recover.

App consistent snapshot frequency is te interval that Azure Site Recovery takes app-consistent snapshots. App-consistent snapshots caputre disk activity, data in memory and any transactions in process to caputre the entire state of a VM.

Update seetings can be set to Manual or Allow ASR to manage. For this example, we have set it at Allow ASR to manage which will automatically keep the extension deployed onto each machine up tp date.

(9) Once you have configured all application settings, click on Enable Replication. 

• Once Azure Site Recovery begins the replication process, bekow mentioned steps would be taken:
• Azure Site Recovery installs the ASR extension onto each VM to communicate with them.
• The Azure Site Recovery extension registers itself with the Site Recovery Vault.
• Azure Site Recovery creates a resource group with the suffix of -asr
• Azure Site Recovery creates the managed disks for each VM and a VNet, with names appended with "--asr".
• The vaule begins replicating the VMs while in porcess, disk writes are transferred to a local storage account, which acts as a dedicated cache in the source region. These writes are processed and then sent to your selected region for failover.
• The vault processes the local storage data and sends it to a stroage account created by ASR or managed disks in the destination region.
• Every five minutes, ASR creates crash-consistent recovery points. A crash-consistent snapshot contains only what was on the disk at the time of the snapshot. It does not include anything in memory, ulike an app-consistent snapshot.

(10) Naviage to the Azure Site Recovery resource group to see all of the resources the Azure Site Recovery has just created.

Read my next article understand how to implement Test Failover with Azure Site Recovery, which is in the continuation of this article.