Having a virtualised MediaAgent / VSA Access Node would allow you to leverage the VMware HotAdd Transport Mode, which can significantly improve backup performance when compared to NBD.

HotAdd does introduce some complexities, so as a general rule, I typically recommend using NBD if the performance is already adequate. If you want to explore HotAdd, this covers it quite well: HotAdd Transport for VMware (commvault.com) 

Thanks for the quick reply,

Just checking the docco, and it refers to a “Proxy” quite often.
My understanding, is that the MA becomes the proxy, is that correct?

I seem to remember other configs actually needing a dedicated Proxy, but i think that was where we were driving hardware snapshots through the storage layer (IntelliSnap days etc).

But if we have ESX, with an ESX-hosted MA backing up VM’s in the same vCentre environment I think the MA is the Proxy, and we don’t need an additional one.

Do I have that correct.

Thanks

Your MediaAgent will need the Virtual Server Agent (VSA) installed before it can be used as a VSA Access Node (Proxy). Whether or not you’ll require additional VSA Access Nodes will be dependent on the number and size of virtual machines you’re protecting, and how heavily utilised your MediaAgent is.

Yep - looks straightforward imo.

Thanks

Media Agent and Virtual Server Agent proxy are two separate modules… It does not change the fact that in most cases they are installed together. In virtualized environment, having both modules installed in the same VM is a good choice but, as mentioned earlier, the number of VSA proxies (access nodes)  and media agents (data movers, DDB holders) will be depending on the number of VMs/disks to back up in parallel.