Azure VM Backup Solutions and Features Overview

Azure VM Backup offers a robust solution for protecting your virtual machines. It provides a centralized console for managing backups and recoveries.

Azure VM Backup supports multiple backup types, including application-consistent backups, crash-consistent backups, and file-level backups. You can choose the backup type that best suits your needs.

With Azure VM Backup, you can back up your virtual machines to a recovery services vault, which stores your backups securely. This vault is a central location for managing all your backups and recoveries.

Azure VM Backup integrates with Azure Monitor, allowing you to monitor and troubleshoot backup operations. This integration provides visibility into backup status and allows for quick issue resolution.

Azure Backup completes a backup for Azure VMs according to the backup schedule you specify. This process involves several steps, starting with the installation of a backup extension on the VM if it's running.

The type of backup you choose affects the process. If you opt for application or file-system consistent backups, the VM needs a backup extension to coordinate the snapshot process. If you prefer crash-consistent backups, no agents are required in the VMs.

The backup process also varies depending on the type of VM. For Windows VMs, Azure Backup coordinates with Windows Volume Shadow Copy Service (VSS) to take an app-consistent snapshot. For Linux VMs, Backup takes a file-consistent backup, which requires manual customization of pre/post scripts for app-consistent snapshots.

Here are the key differences in the backup process for Windows and Linux VMs:

After the snapshot is taken, Azure Backup transfers the data to the vault.

The backup process for Azure VMs is a straightforward one. Azure Backup starts a backup job according to the backup schedule you specify.

For Azure VMs that require application or file-system consistent backups, a backup extension needs to be installed on the VM to coordinate the snapshot process. This extension is installed on the VM during the first backup if the VM is running.

Azure Backup coordinates with Windows Volume Shadow Copy Service (VSS) to take an app-consistent snapshot of the VM for Windows VMs that are running. For Linux VMs, a file-consistent backup is taken instead.

Here's a summary of the backup process for Azure VMs:

Each Azure VM in a cluster is considered an individual Azure VM, so all backup operations apply as per individual Azure VMs.

Redstor's Azure VM Pro has zero impact on the machine's resources being protected, allowing the production environment to remain at peak performance for users and customers.

Redstor’s proprietary InstantData technology enables you to recover your VMs with no downtime. This means you can quickly get back to work while your less critical data is recovered in the background.

With InstantData, sparse files of all your data become accessible upon initiating a recovery, eliminating the need to wait for the entire system to be rebuilt.

BDRSuite allows for quick restore of entire Azure VM to any subscription and resource group available within your account.

Instant recovery is made possible with automated snapshots, which enable quick VM recovery or Volume recovery in case of data loss or system failure.

Here are the key benefits of automated snapshots:

Azure Backup uses native APIs to create copies of Azure virtual machines for backup, offering flexibility and scalability by allowing you to store backup data in either local or cloud storage.

This method eliminates the need for additional agents on the VMs, making it an efficient choice for organizations with many virtual machines to manage.

BDRSuite leverages Azure's native APIs and snapshots to create copies of Azure virtual machines for backup, as mentioned in Example 5.

With agentless backup, you can store backup data in local or cloud storage, giving you more control over your data management.

Here are the benefits of agentless backup in a nutshell:

Centralized backup management is key to simplifying operations and eliminating manual job scheduling. This approach allows you to manage and protect data across your entire estate, whether in Azure, on-premise, or a range of SaaS applications.

Azure Backup backs up the secrets and KEK data of the key version during backup, and restores the same. This ensures that your sensitive information is properly protected.

Application consistent VM backup is supported, but it requires VSS to freeze I/O and ensure disk snapshots are consistent. This is crucial for maintaining data integrity.

Azure Backup uses Storage Service Encryption (SSE) for at-rest encryption of Azure VMs, providing an additional layer of security for your data.

SSE comes in two types: SSE with platform-managed keys, which is the default for all disks in your VMs, and SSE with customer-managed keys, where you manage the keys used to encrypt the disks.

Azure Disk Encryption integrates with BitLocker encryption keys (BEKs) and Azure Key Vault key encryption keys (KEKs) to provide an extra layer of security.

Both BEKs and KEKs are backed up and encrypted, providing an added layer of protection against unauthorized access.

Here's a breakdown of the encryption methods supported by Azure Backup:

Only users with the necessary permissions can back up and restore encrypted VMs, keys, and secrets, ensuring that your data remains secure.

Your backups are stored in a resource group within your Azure subscription, and can be securely replicated to a cloud of your choice for added resilience.

Azure VM Pro allows you to test your disaster recovery plan as often as needed, at no extra cost.

This means you can recover a VM's data to the original machine or a new one at any time, without disrupting your production environment.

Centralized management makes your life easier by eliminating manual job scheduling and simplifying operations with policy-based management across your entire estate.

You can centrally manage and protect data in a broad range of environments, whether in Azure, on-premise, or a range of SaaS applications.

Manual job scheduling is a thing of the past with centralized management, freeing up time for more important tasks.

Azure Backup backs up the secrets and KEK data of the key version during backup, and restores the same, ensuring consistent data protection.

Removing a disk will simply not run any snapshot or data transfer for the removed disk, which can be a relief for system administrators.

The number of disks included in the restore point will differ depending on the VM state at the time of the backup, so be sure to keep this in mind when planning your backups.

To enable backup for a VM, you'll need to have specific permissions. If you're a VM contributor, you're good to go, but if you're using a custom role, you'll need to have the right permissions in place.

To get started, you'll need the Microsoft.RecoveryServices/Vaults/write permission, which allows you to write to the Recovery Services vault. You'll also need the Microsoft.RecoveryServices/Vaults/read permission, which gives you read access to the vault.

Additionally, you'll need the Microsoft.RecoveryServices/locations/* permission, which grants you access to locations. This is important if your Recovery Services vault and VM have different resource groups.

Here are the specific permissions you'll need to enable backup on a VM:

Don't forget, if your Recovery Services vault and VM are in different resource groups, you'll need to have write permissions in the resource group for the Recovery Services vault.

Backup performance can be affected by several factors, including adding a new disk to a protected Azure VM, which can increase total backup time to over 24 hours due to initial replication of the new disk.

Fragmented disks can also slow down backup operations, while disk churn of more than 200 GB can take over eight hours to complete.

Backup versions, such as the Instant Restore version, can also impact performance, especially if you've deleted a backup snapshot, which can cause the backup operation to exceed 24 hours.

To optimize restore performance, select a storage account that isn't loaded with other application data, and be aware that the total restore time depends on the Input/output operations per second (IOPS) and the throughput of the storage account.

Here are some best practices to keep in mind:

Snapshot Consistency is a key aspect of Azure Backup, and it's essential to understand the different types of consistency to ensure reliable data recovery.

Azure Backup offers three types of snapshot consistency: Application-consistent, File-system consistent, and Crash-consistent.

The default setting for Azure Backup is Application-consistent, which captures memory content and pending I/O operations, ensuring that apps start in a consistent state when recovering a VM.

File-system consistent backups provide consistency by taking a snapshot of all files at the same time, but apps need to implement their own "fix-up" mechanism to ensure restored data is consistent.

Crash-consistent snapshots capture only the data that already exists on the disk at the time of the backup operation, and data in read/write host cache isn't captured.

Here's a summary of the three types of snapshot consistency:

When configuring VM backups, it's essential to modify the default schedule times set in a policy. For example, if the default time is 12:00 AM, increment the timing by several minutes to optimize resource usage.

Modifying the schedule can make a big difference in backup performance. If a VM is undergoing incremental backup and a new disk is added, the backup time will increase due to initial replication of the new disk, along with delta replication of existing disks.

To avoid this, consider the following best practices:

By following these best practices, you can ensure optimal backup and restore performance for your VMs.