Optimize Veeam configuration for use with VMware VSAN
You can use any VMware Backup Proxy to backup VMs from your VSAN cluster. You may however want to reduce the network traffic generated from the data being read by the backup proxy.
Configure virtual proxies to make use of Hotadd. This can be any supported Windows server deployed as a VM on a host that has access to the VSAN cluster; the Proxy VM's disks should also be located on the protected VSAN cluster. If you have a backup proxy on each ESXi host in the VSAN cluster, Veeam Backup & Replication chooses the most appropriate backup proxy to reduce the backup traffic on the VSAN cluster network. To ensure this always happens you can configure a DRS VM-Host rule on each host to keep the proxy resident on each host.
For more information on backing up VMs on VSAN using Virtual Appliance Mode see the Help Center sections covering the Requirements for Backup Proxy Servers as well as the Virtual Appliance Mode for VMs on VSAN