Route Table
Understanding VPC Route Tables
ℹ️ What is a Route Table?
A route table is a critical VPC component that contains a set of rules (routes) that determine where network traffic from your subnet or gateway is directed. Each route table controls the routing for its associated subnets, making it essential for network traffic management within your VPC.
Route Table Fundamentals
Route tables consist of route entries that specify:
- Destination - The destination CIDR block where you want traffic to go
- Target - The gateway, network interface, or connection through which to send the traffic
When you create a VPC, AWS automatically creates a main route table that includes a default local route for internal VPC communication.
⚠️ Important Considerations
Every subnet in your VPC must be associated with a route table. If you don’t explicitly associate a subnet with a route table, the subnet is automatically associated with the main route table.
Default Local Route
For example, if you create a VPC with CIDR block 10.10.0.0/16 containing two subnets (10.10.1.0/24 and 10.10.2.0/24), the default route table will contain:
- Destination:
10.10.0.0/16 - Target:
local
💡 Pro Tip
The local route enables communication between all resources within the same VPC, regardless of which subnet they’re in. This route is automatically added to all route tables in your VPC and cannot be modified or removed.
