Good afternoon.  There is no maximum number for either.  It really depends on the performance of your network/storage network and how robust your proxies are.  

@Mentee, @Orazan is right, there is no recommendation in terms of size. However you should consider the streams count for them. If the stream count is small and the VM number high then you may not complete a backup in the desired time frame. However, when increasing the streams you have to also think about the VMware/other hypervisor, can it handle that much activity at once? Will you get throttled by the cloud vendor etc...

Also for the VSA proxies (Access Nodes), the CPU and RAM is also going to limit how many streams can be used. So if you do increase the streams then look though our documentation for the best size for your Access Nodes and how that can be balanced with the number of nodes:

https://documentation.commvault.com/11.26/expert/97216_backup_workload_distribution.html

Also for cloud based protection you can use the auto scaling Access Nodes feature to save costs….https://documentation.commvault.com/11.25/essential/111430_automatic_scaling_for_amazon_access_nodes.html

Hi,

If I may add, another interesting thing to look at is the maximum devices that you can attach to a proxy/Proxy VM, which would be (in short) around 20, depending on the backup mode..

Like your proxy has 3 disks drives, and the VMs you need to backup have 5 disks each (VMDKs), if you configure per VM subclient 10 streams, then when you backup 1 VM, all its VMDKs will be attached to your proxy. This way your proxy could be able to backup 4 VMs in parallel before reaching the max devices attached to a VM limit.

This is a very short explanation, but that’s the idea.