How to Hot Backup VMware Virtual Machine While Running

Q: Can you backup VMware virtual machine while running?

Virtual machines have become the core of IT systems, and need to be backed up regularly to avoid disastrous data loss in the event of unexpected failures. For users that need to run VMs continuously so as to maximize utility and maintain the business continuity, there's an advanced requirement - backup VMware VMs while running (namely hot backup). But can we really do that?

The answer actually depends on how you define the term "backup". As you may know, there are 3 data preserving measures that can be performed while a VM is running. However, they are not all standard backup methods, and some of them have drawbacks.

• VM snapshots: preserve the current state of the VM. Snapshots cannot replace backups since they are not suitable for long-term storage.
• Hot cloning: creates multiple same copies of the VM, but requires a lot of storage spaces and compute resources.
• Hot backup via third-party software: the standard backup method. Creates independent and complete backups that can be encrypted or compressed.

What happens when backup VMware virtual machine while running

While the above 3 methods are able to preserve data while the VM is running, hot backup is not recommended as it can lead to inconsistency.

• Crash-consistent backup: most current backup software creates crash-consistent backups by taking a snapshot before the backup and then backing up the non-incremental VMDK. However, information in memory or in any pending I/O transactions is disregarded, and this is critical in the case of database applications such as Microsoft SQL Server and Microsoft Exchange Server.
• Application-consistent backup: also known as application-aware backup, captures application information both in memory and in pending I/O operations by utilizing Microsoft's Volume Shadow Copy Service (VSS), allowing it to be backed up properly with transactional consistency.

Therefore, you should choose whether to hot backup VMware VMs and the software according to your actual needs. With the above knowledge, you can may your choice accordingly.

Backup VMware virtual machine while running via Snapshot or Clone

In this section I will introduce how to take snapshot of running VM, and how to hot clone VMware ESXi VMs.

• If you just want to perform certain risky operations and are willing to roll back the VM to the state before the operations, take snapshot of running VM can be quick and convenient.
• If you want to create one or multiple same copies of the VM and have enough storage spaces, then hot clone VMware VMs may be a better option for you. 

Before you begin, please try not to make changes to the VM during backup process, and be aware that even then, hot clone will take longer than cold clone.

How to take snapshot of running VM on VMware ESXi

1. Access to vSphere Web Client, go to Virtual Machines page in the left inventory. Right-click on the name of the VM you want to backup, and select Snapshots > Take Snapshot...

2. In the pop-up window, provide a Name and optionally a Description for the snapshot. You can Edit them later in Snapshot Manager.

3. There are 2 more options to check:

✤ Snapshot the virtual machine’s memory: record the VM’s memory, allowing you to roll back the VM to the exact running state when the snapshot was taken, but takes longer. If you leave this option unchecked, then the VM will be powered-off after you roll back.

✤ Quiesce guest file system (needs VMware tools installed): pause the state of the processes that are running, or may modify the information stored on disk when the snapshot was taken, to guarantee the consistency. Quiescing and Memory snapshots are mutually exclusive.

4. Click OK to take the snapshot. You can see the progress in Recent Tasks.

When you restore from a snapshot, you will revert the VM to the state when the snapshot was taken and discard all changes afterwards.

How to hot clone running VMs via VMware vCenter Converter Standalone

VMware vCenter Converter Standalone provides an easy-to-use solution that automates the process of creating VMware virtual machines from physical machines (running Windows and Linux) and other virtual machine formats. With it, you can hot clone running VMs.

Note: the new version of VMware vCenter Converter 6.3.0
To protect customers from legacy technologies that do not meet security and stability standards, VMware once removed vCenter Converter from the Product Downloads list, but also promised a renewed version. Now here it comes, the new vCenter Converter 6.3.0, compatible with vSphere 7.0 and ESXi 7.0!
You can go to the official product page to download it.

1. Launch VMware Converter Standalone, click Convert machine on the toolbar.

2. In the pop-up Conversion wizard, select the Source Type as Powered-on machine, and specify the server connection information. Click Next.

3. On Source Machine page, select the running VM you want to clone. And then click Next.

4. On Destination System page, select destination type. Here I select VMware infrastructure virtual machine and provide VMware infrastructure server details. Click Next.

5. On Destination Virtual Machine page, provide a Name for the new VM, and click Next.

6. On Destination Location page, select a datastore and Virtual Machine version. Click Next.

7. On Options page, browse the Current settings and Edit them. Then you can click Next.

8. On Summary page, review the information and click Finish to start VM cloning. You can see the progress in the Recent Tasks interface.

Among the available ways to backup VMware virtual machine while running, snapshots cannot be considered as backups because they do not create an independent copy of the VM and can affect the performance. You can also perform hot clone via VMware converter, but creating a new VM requires virtual disk space, and cannot be easily stored to other locations. It seems that they are both less convenient than independent backup files.

Therefore, to better protect your important business data, professional backup software may also be a good choice.

Reliable and free solution to hot backup VMware VMs while running

In the premise that snapshots cannot properly replace backups, many users choose to use professional backup solutions for better protection over their important virtual machines. Here I will introduce AOMEI Cyber Backup, the free VMware backup software for the following advantages:

◆ Easy-to-use: It is an agentless backup solution with a very intuitive central console. You can achieve VM backup and restore with simple clicks.
◆ Image-based VM backup: Create independent, full backups that can be used to restore entire, runnable VMs.
◆ Different backup methods: It supports backup types of full/differential/incremental, and enables you to backup virtual machines on both running and off state.
◆ Auto backup: Create a schedule backup to make it autorun daily/weekly/monthly.
◆ Centalized backup: Backup virtual machines from a central console without installing agents on each VM.
◆ Support free ESXi: AOMEI Cyber Backup supports both paid and free versions of VMware ESXi.

Next I will demonstrate how to hot backup VMware virtual machines while running. Before getting started, you can hit the button to download and enjoy the free edition:

*You can choose to install this VM backup software on either Windows or Linux system.

How to backup VMware ESXi virtual machine while running

To use the freeware for hot backup, please first launch AOMEI Cyber Backup and navigate to Source Device > VMware > + Add VMware Device to add vCenter or Standalone ESXi host as the source device. And then click … button next to the host name to Bind Device.

After successful binding, you can start backing up the VMs on these devices at any time.

Navigate to Backup Task and click + Create New Task.

In the pop-up task tab, there are 6 settings to complete a backup task.

1. Task Name. You can leave the default unique task name, or change the name as you like.

2. Backup Type. Select to perform VMware ESXi Backup.

3. Device Name. Click Select + to select a host and single or multiple VMs you want to backup. Click OK to save.

You can select running VMs to back up in this step. With AOMEI Cyber Backup you can hot backup VMware virtual machines while running without any worries.

4. Target. Click Select + to add a destination location for storing the backup.

The used storage paths will be saved in Favorite Storage for easy finding. Besides, you can Create a new local path or Create a new network path in this step.

5. Schedule. Click the context to change the default backup schedule.

You can choose to perform full, incremental or differential backup daily, weekly, or monthly, and specify a start time, end time and intervals.

If you only want to perform the backup once, you can turn off the Enable Schedule button.

6. Start Backup. If you enabled backup schedule, you can select to Add the schedule and start backup now, or Add the schedule only. You can check the backup progress and details in Tasks.

✎While the Free Edition can cover most of VM backup needs, you can also upgrade to enjoy:
Backup cleanup: For better manage the disk space, you can reset the full, incremental, and differential backup retention period, and select to always retain the first full backup of every week, month, season, or year, according to your needs.

Summary

For most times, it is not recommended to backup VMware virtual machine while running, because this will result in inconsistency. So currently, there are only 3 available ways to implement this.

However technically speaking, snapshot and hot clone cannot be taken as standard backup methods, because they do not back up VMs as independent backup files. In this regard, maybe a comprehensive VM backup tool can better help you.

AOMEI Cyber Backup can back up VMware virtual machines while running, and except for VMware/Hyper-V, it also supports Microsoft SQL backup, allowing you to seemlessly safeguard your databases. If you want basic data backup & restore features to protect your virtual machines, AOMEI Backupper is also worth a try.