TL;DR: If your upstream peers are drowning in /32s from NATs and VIPs—or you just want faster convergenc. NSX‑T Route Aggregation lets you advertise neat summaries (e.g., 10.10.0.0/16) northbound and suppress the noise.
When you announce a /32 to your core routers, it’s likely they won’t get accepted. The smallest internet routed ipv4 is a /24 scope. Internally in your network, you can have as many /32 routes as you or your route table will allow.
By default, NSX-T won’t do any route aggregation, so it’s all /32 routed addresses. An example could look like this:
This picture is more to show you have it actually works, but let’s go with the route table was full of /32 addresses and we wanted to make it simpler. We could introduce the route aggregation without out summary.
Now we can see both the /24 and the /32 routes for the 185.66.12.0 scope. To make the routetable even simpler, we can choose to summarize. That would put all the /32 routes under the larger /24 scope.
