As with all things in life, "it depends".  In our case, we have multiple VMware clusters, backed up by Avamar.  Some clusters are on different storage arrays, and in turn, different data stores.  For simplicity, our VMware admins wanted some proxies to be "local" to a given cluster/datastore combo, so we deployed different proxies on different vCenters.  When then associated different proxies with different datastores, hence, we use different proxies to backup different VMs.  Because of this, we don't do the Select All when setting up our proxies; we only have proxies backup VMs on their assigned datastores (we use simple hostnames on the proxies that make it easy to tell).

If you can expect that proxies will always have access to all of the datastores, then you should definitely just do the Select All button.  However, if you expect you might need some "fine tuning", just choose the datastores you need.

Let us know if that helps!

Karl

Thanks Karl.  That clarifies it for me.