
All-in-one FM which request all DC virtualization managed by this one FM. for example, you have 3 DC, each DC have one virtualization environment(2 FusionCompute and 1 Vcenter), you can choose all these environment managed by All-in-one FM.

for local FM, it's managed local DC virtualization environment only. Then if there are lots of DC, can install one FM to management all DC FM.