A backup proxy is an architecture component that sits between the backup server and other components of the backup infrastructure. While the backup server administers tasks, the proxy processes jobs and delivers backup traffic.
Basic backup proxy tasks include the following:
- Retrieving VM data from the production storage
- Sending it to the backup repository (for example, if you run a backup job) or another backup proxy (for example, if you run a replication job)
Backup Proxy Transport Modes
Depending on the type of backup proxy and your backup architecture, the backup proxy can use one of the following data transport modes:
- Direct storage access
- Virtual appliance
If the VM disks are located on the storage system and the storage system is added to the Veeam Backup & Replication console, the backup proxy can also use the Backup from Storage Snapshots mode.
Backup Proxy Deployment
By default, the role of the proxy is assigned to the backup server itself. However, this is sufficient only for small installations with low traffic load. For large installations, it is recommended to deploy dedicated backup proxies.
Use of backup proxies lets you easily scale your backup infrastructure up and down based on your demands. To optimize performance of several concurrent jobs, you can use a number of backup proxies. In this case, Veeam Backup & Replication will distribute the backup workload between available backup proxies. You can deploy backup proxies both in the primary site and in remote sites.
To deploy a proxy, you need to add a Windows-based server to Veeam Backup & Replication and assign the role of a backup proxy to the added server. Backup proxies run light-weight services that take a few seconds to deploy. Deployment is fully automated. Veeam Backup & Replication installs the necessary components and starts the required services on it.
Backup Proxy Services and Components
The backup proxy uses the following services and components:
- Veeam Installer Service is an auxiliary service that is installed and started on any Windows server once it is added to the list of managed servers in the Veeam Backup & Replication console. This service analyzes the system, installs and upgrades necessary components and services depending on the role selected for the server.
- Veeam Data Mover is a component that performs data processing tasks on behalf of Veeam Backup & Replication, such as retrieving source VM data, performing data deduplication and compression, and storing backed up data on the target storage.
Requirements for Backup Proxy
A machine performing the role of a backup proxy must meet the following requirements:
- The machine must meet the system requirements. For more information, see System Requirements.
- The role of a backup proxy can be assigned to a dedicated Microsoft Windows server (physical or virtual).
- You must add the machine to the Veeam Backup & Replication console as a managed server.
The primary role of the backup proxy is to provide an optimal route for backup traffic and enable efficient data transfer. Therefore, when deploying a backup proxy, you need to analyze the connection between the backup proxy and storage with which it is working. Depending on the type of connection, the backup proxy can be configured in one of the following ways (starting from the most efficient):
- A machine used as a backup proxy should have direct access to the storage on which VMs reside or the storage where VM data is written. This way, the backup proxy will retrieve data directly from the datastore, bypassing LAN.
- The backup proxy can be a VM with HotAdd access to VM disks on the datastore. This type of proxy also enables LAN-free data transfer.
- If neither of the above scenarios is possible, you can assign the role of the backup proxy to a machine on the network closer to the source or the target storage with which the proxy will be working. In this case, VM data will be transported over LAN using NBD protocol.
Limitations for Backup Proxy
The change block tracking mechanism (CBT) is disabled if you back up proxies that use the Virtual appliance (HotAdd) mode to process VM data. For more information on CBT, see Changed Block Tracking.