Python Network Programming

Route tables and route targets

Routing is one of the most important topics in network engineering. It is worth looking at it more closely. We already saw that we had an implicit router and the main routing table when we created the VPC. From the last example, we created an internet gateway, a custom routing table with a default route pointing to the internet gateway, and associated the custom routing table with a subnet.

The concept of the route target is where VPC is a bit different than traditional networking. In summary: 

• Each VPC has an implicit router
• Each VPC has the main routing table with the local route populated
• You can create custom-routing tables
• Each subnet can follow a custom-routing table or the default main routing table ...