Architecture Overview

The Veeam Backup for Microsoft Azure infrastructure includes the following components:

Backup Appliance

The backup appliance is a Linux-based Azure VM where Veeam Backup for Microsoft Azure is installed. The backup appliance performs the following administrative activities:

The backup appliance also maintains the configuration database that stores data collected from Veeam Backup for Microsoft Azure for the existing backup policies, protected Azure resources, launched worker instances, connected Microsoft Azure accounts and so on.

Backup Appliance Components

The backup appliance uses the following components:

Backup Repositories

A backup repository is a folder in a blob container where Veeam Backup for Microsoft Azure stores image-level backups of Azure VMs and Azure SQL databases.

To communicate with a backup repository, Veeam Backup for Microsoft Azure uses Veeam Data Mover — the service that runs on a worker instance and that is responsible for data processing and transfer. When a backup policy addresses the backup repository, the Veeam Data Mover establishes a connection with the repository to enable data transfer.

Important

Backups are stored in backup repositories in the native Veeam format and must be modified neither manually nor by 3rd party tools. Otherwise, Veeam Backup for Microsoft Azure may fail to restore the backed-up data.

Encryption on Repositories

For enhanced data security, Veeam Backup for Microsoft Azure allows you to enable encryption at the repository level. Veeam Backup for Microsoft Azure uses the same encryption standards as Veeam Backup & Replication to encrypt backups stored in backup repositories. To learn what encryption standards Veeam Backup & Replication uses to encrypt its data, see the Encryption Standards section of the Veeam Backup & Replication User Guide.

To learn how to enable encryption at the repository level, configure the repository settings as described in section Adding Backup Repositories, and choose whether you want to encrypt data using a password or using an Azure Key Vault cryptographic key.

Limitations for Repositories

To use a blob container as a target location for backups, you must connect to an Azure storage account in which this blob container resides, as described in section Adding Backup Repositories.

Veeam Backup for Microsoft Azure supports the following types of Azure storage accounts:

Storage Account Type

Supported Performance Tiers

Supported Access Tiers

General-purpose V2

Standard

Hot, Cool, Archive

BlobStorage

Standard

Hot, Cool, Archive

 

Important

Consider the following limitations for storage accounts:

  • Veeam Backup for Microsoft Azure does not support creation of backup repositories in storage accounts with enabled blob soft delete option.
  • Veeam Backup for Microsoft Azure does not support creation of backup repositories in storage accounts with enabled data redundancy (GZRS, RA-GZRS) option.
  • Veeam Backup for Microsoft Azure does not support archive tiering of storage accounts with enabled zone data redundancy (ZRS, GZRS, RA-GZRS) option.

Worker Instances

A worker instance is an auxiliary Linux-based virtual machine that is responsible for the interaction between the backup appliance and other components of the Veeam Backup for Microsoft Azure infrastructure. Worker instances process backup workload and distribute backup traffic when transferring data to backup repositories.

Veeam Backup for Microsoft Azure automatically launches worker instances to process Azure VMs and Azure SQL databases when performing a backup or restore operation, and keeps the instances running for the duration of the operation. Veeam Backup for Microsoft Azure launches one worker instance per each Azure resource specified in a backup policy or restore task. To minimize cross-region traffic charges and to speed up the data transfer, depending on the performed operation, Veeam Backup for Microsoft Azure launches worker instances in the following locations:

Operation

Worker Instance Location

Default Worker Profile

Creating image-level backups of Azure VMs

Azure region in which a processed Azure VM resides

Standard_F2s_v2, 2 CPU, 4 GB RAM

Creating image-level backups of Azure SQL databases

Azure region in which a SQL Server hosting the processed database resides

Azure file share indexing

Azure region in which a processed file share resides

Creating archived image-level backups of Azure VMs

Azure region in which an archive backup repository storing backed-up data resides

Standard_E2_v5, 2 CPU 16 GB RAM

Creating archived image-level backups of Azure SQL databases

Azure region in which an archive backup repository storing backed-up data resides

Performing health check for created restore points

Azure region in which a target backup repository resides

Standard_F2s_v2, 2 CPU, 4 GB RAM

Applying retention policy settings to created restore points

Azure region in which a backup repository with backed-up data resides

Restoring Azure VMs and Azure SQL databases

Azure region in which the restored Azure VM or SQL Server hosting the restored database resides

Restoring individual virtual disks of Azure VMs

Azure region in which the restored virtual disk resides

File-level restore from cloud-native snapshots

Azure region in which a cloud-native snapshot resides

File-level restore from image-level backups

Azure region in which a backup repository storing backed-up data resides

Worker instances are launched based on worker configurations and profiles that can be created either automatically by Veeam Backup for Microsoft Azure, or manually by the user as described in Managing Worker Instances.

Worker Instance Components

A worker instance uses the following services:

  • Veeam Data Mover — the service that performs data processing tasks. During backup, the Veeam Data Mover service retrieves data from snapshots and stores the retrieved data to backup repositories. During restore, the Veeam Data Mover transfers backed-up data from backup repositories to the target location.
  • File-level recovery browser — the web service that allows you to find and save files and folders of a backed-up Azure VM to a local machine. The File-level recovery browser is installed automatically on every worker instance that is launched for file-level recovery.

For more information on recovering files of Azure VMs using the File-level recovery browser, see Performing File-Level Recovery.

Note

By design, Veeam Backup for Microsoft Azure installs the unattended-upgrades package on every launched worker instance. This package automatically sends requests to the Ubuntu Security Update repository (security.ubuntu.com) to get and install security updates on the worker instance. Due to technical limitations, you can neither configure nor disable these updates in the current version of Veeam Backup for Microsoft Azure.

Security Certificates for Worker Instances

Veeam Backup for Microsoft Azure uses self-signed TLS certificates to establish secure communication between the web browser on a user workstation and the File-level recovery browser running on a worker instance during the file-level recovery process. A self-signed certificate is generated automatically on the worker instance when the recovery session starts.

Requirements for Worker Instances

For every Azure region where worker instances will be launched, you must specify a virtual network, subnet and a security group to which the worker instances must be connected. Otherwise, Veeam Backup for Microsoft Azure will be able neither to launch worker instances nor to perform the required data protection and disaster recovery operations.

To learn how to configure network settings for worker instances, see Adding Worker Configuration.