What is VMware Replication and how it works
VMware vSphere Replication is designed to replicate virtual machines within the same site or a remote site to achieve fast disaster recovery. It is first introduced in VMware vSphere 5.1 Essentials Plus Kit as a built-in feature. It allows you to configure Recovery Point Object (RPO) between 5 minutes and 24 hours for replication intervals.
VMware Replication extends the recovery capabilities and offers an efficient VM protection solution in vCenter Server which replicates the running virtual machine to another location for data protection. At the same time, for consistent recovery in Microsoft, Hyper-V replica ensures the VM safety using Volume Shadow Copy Service.
So, how to perform VMware replication efficiently? In this article, I will introduce the vSphere Replication best practices for setting, configuration and recovery.
How should you set up vSphere Replication
For VMware Replication, it can be used in testing, impending failure or unexpected disaster recovery and allows you to restore virtual machines within several clicks in the vSphere Web Client.
For vSphere Replication best practices, you have to focus on the followings when you start setting up vSphere Replication.
1. Set up Multiple Point in Time (MPIT) Recovery
Keeping multiple replication makes it easier to restore a virtual machine to a specific point in time. If you accidentally lose data in the recent replication, you don't have to worry about overall data loss, making it safer to protect the virtual machine.
However, for the number of recovery points, more is not better. vSphere Replication can support up to 24 recovery points, and each time point consumes the storage, so creating so many recovery points may take so much time to consolidate snapshots after recovery and degrade the performance of virtual machine.
2. Prepare sufficient disk space on the target site
VM replication requires enough space for replication storage on the target datastore. Insufficient disk space may result in replication failure. So, set aside enough space to store replication. You can create an alarm that alerts you about insufficient storage capacity at the target site.
3. Use Changed Block Tracking
Changed Block Tracking is a technology first introduced in vSphere 4.X. It tracks the exact changes since the last backup and replicates the changed data to the replication virtual machine in time.
Best practices to protect VM with vSphere Replication
Replication is a necessary solution for VM protection. This part will introduce the how to utilize vSphere Replication and the detailed steps to replicate a virtual machine to another location successfully.
Step 1. Deploy vSphere Replication
Before you start use it, it is important to deploy vSphere Replication Appliance correctly at the source and the target sites and use “Deploy OVF Template”.
Step 2. Configure Replication for a VM
Configuring vSphere Replication correctly is crucial to replicate a virtual machine to another location, which determines whether you can successfully implement the VMware vSphere Replication best practices.
Navigate to vCenter, right click a virtual machine you want to replicate and select All vSphere Replication Actions >> Configure Replication.
Target site: Select target site for VM replication
Target location: Specify a datastore to store the replicated files.
Replication settings: Set up the Recovery Point Object from 5 minutes to 24 hours, and select Enable point in time instances.
Ready to complete: Review the configured information, click Finish to close the wizard
Step 3. Recover a replicated VM
After configuration, you can easily monitor the status of all incoming and outcoming replications to the target site through the Summary screen.
If some accidental events happened to your original virtual machines, you can recover the replicated VM at the target site to keep business continuity.
• Log in vSphere Web Client or vSphere Client, and access to the target site.
• Click Site Recovery >> Open Site Recovery. Then select a site pair and click View Details.
• Click Replication and select a replication from Incoming. Then click Recovery.
• Recovery Options: Select Recover with recent changes or Recover with latest available data.
Recover with recent changes: It is generally used on the power-of state of VM on the source site when you plan to shut down virtual machines. It will perform a full synchronization of the VM from the source site to the target site to avoid data loss.
Recover with latest available data: It allows you to recover the virtual machine when the source VM is on the power-on state. It uses the latest replication without synchronization which may lose the data that has changed since the most recent replication.
• Folder: Select the recovery folder for the virtual machine at the target site.
• Resource: Specify the cluster, host and resource pool for recovery.
• Ready to complete: Review the settings, and click Finish.
How to use backup and recovery for VM protection
As we know, replication is generally used for fast disaster recovery. If you want to ensure business continuity in the event of an unexpected disaster, you can choose replication. However, backup is more commonly used for long-term data security. Backup provides a stable and secure method for VM protection which is different from replication that only offers 24 recovery points for a short-term protection. So, performing backup and recovery is a good solution for VM replication. Using a professional backup software which safeguards your business for a long term.
For VMware backup software, I will use AOMEI Cyber Backup as an instance to show you how to achieve instant VM protection in this part.
This software can help you to do the followings easily.
Automatic VMware Backup: Auto backup virtual machines on regular basis to protect VMware workloads continuously.
Restore from Any Point easily: Restore VM from any backup point directly and quickly, eliminating the need to restore a full backup plus each subsequent backup point.
Save storage: Store VM files to local or network instead of setting aside extra space for replication, and offer Backup Retention Policy to delete useless backups to save space.
Lower cost: It’s economical and no need to access to vCenter.
Steps to perform backup and recovery
1. Install AOMEI Cyber Backup. Click Backup Task >> Create Backup Task.
2. Select virtual machines for backup and backup Target as a local or network place.
3. Schedule the backup task, select full / incremental /differential backup and specify the time for auto backup.
4. Specify retention policy for each backup to delete unwanted backup files to free up space.
5. Backup the main screen, click Restore to perform fast recovery when the original VM corrupted. Select Restore to original or new location and easily configure the new VM.
Within several clicks, you can simply obtain a secure backup of multiple virtual machines, and restore VM fast to different site. It helps you recover VM in the event of a disaster and protects VM data security.
Frequently asked questions about VMware Replication
Q: Does vSphere replication use snapshots?
A: vSphere Replication retains a number of snapshot instances of the virtual machine on the target site based on the retention policy that you specify. vSphere Replication supports a maximum of 24 snapshot instances. After you recover a virtual machine, you can revert it to a specific snapshot.
Q: What is the difference between vSphere replication and SRM?
A: vSphere Replication license is included in vSphere Enterprise Plus, while SRM is an independent product and is a per VM or per CPU (as part of vCloud Suite Enterprise) license.
This article introduces the VMware vSphere Replication best practices. VMware vSphere Replication makes a full synchronization of the source virtual machine and provides fast recovery at the target site to prevent virtual machines from disaster.
In addition to allowing fast recovery, a professional backup software is also efficient to offer data security insurance for a long-term with an economical cost.