When Veeam Backup & Replication is initially installed, the backup server coordinates all job activities
and handles data traffic itself. That is, when you run a backup, replication, VM copy, VM migration job
or perform restore operations, VM data is moved from source to target through the backup server.
This scenario is acceptable for virtual environments where few backup jobs are performed; in largescale
environments, however, the workload on the backup server will be significant.
To take the workload off the backup server, Veeam Backup & Replication uses backup proxies. A
backup proxy is an architecture component that sits between data source and target and is used to
process jobs and deliver backup traffic. In particular, the backup proxy tasks include retrieving VM
data from the production storage, compressing and 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). As the data
handling task is assigned to the backup proxy, the backup server becomes the “point of control” for
dispatching jobs to proxy servers.
The role of a backup proxy can be assigned to a dedicated Windows server (physical or virtual) in your
virtual environment. You can deploy backup proxies both in the primary site and in remote sites. 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.
Use of backup proxies lets you easily scale your backup infrastructure up and down based on your
demands. Backup proxies run light-weight services that take a few seconds to deploy. Deployment is
fully automated — Veeam Backup & Replication installs the necessary components on a Windowsbased
server when you add it to the product console. As soon as you assign the role of a backup proxy
to the added server, Veeam Backup & Replication starts the required services on it.
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.
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 or Network. 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.
You can explicitly select the transport mode or let Veeam Backup & Replication replication
automatically choose the mode. For details, see Transport Modes and Backup from Storage Snapshots.