Question

How does networking work in AWS Fargate?

Answer 1

In AWS Fargate, networking works similarly to other container orchestration platforms like Amazon ECS or Amazon EKS. Fargate tasks are deployed within a Virtual Private Cloud (VPC) and have access to various networking features provided by AWS. Here's how networking works in AWS Fargate:

1. Virtual Private Cloud (VPC):

   • Fargate tasks run within a VPC, which allows you to define a virtual network environment in which your Fargate tasks operate.
   • You can create and configure subnets, route tables, internet gateways, and other networking components within your VPC to control network traffic and access to and from your Fargate tasks.

2. Task Networking:

   • Each Fargate task is assigned its own Elastic Network Interface (ENI) with a private IP address within your VPC.
   • Fargate supports two networking modes:
     • awsvpc: Each task gets its own ENI and has full networking isolation. This mode provides the highest level of network performance and security and is the recommended networking mode for Fargate tasks.
     • bridge: Tasks share the networking stack of the underlying host instance or cluster. This mode is similar to traditional Docker networking but offers less isolation and security compared to the awsvpc mode.

3. Internet Access:

   • By default, Fargate tasks deployed in a private subnet within a VPC do not have internet access.
   • To enable internet access for your tasks, you can configure a NAT gateway or NAT instance in a public subnet, and then route traffic from your private subnet to the NAT gateway or NAT instance.

4. Load Balancing:

   • You can use Elastic Load Balancing (ELB) services such as Application Load Balancer (ALB) or Network Load Balancer (NLB) to distribute traffic to your Fargate tasks.
   • When deploying tasks with Fargate, you can associate them with an ALB or NLB to expose your applications to incoming traffic from clients or other services.

5. Service Discovery:

   • Fargate tasks can use AWS Cloud Map or Amazon Route 53 for service discovery within your VPC or across multiple VPCs.
   • Cloud Map allows you to define custom names for your services and automatically updates DNS records as tasks come and go.

6. Security Groups and Network Access Control Lists (ACLs):

   • You can use security groups and network ACLs to control inbound and outbound traffic to and from your Fargate tasks.
   • Security groups act as stateful firewalls at the instance level, while network ACLs act as stateless firewalls at the subnet level.

Overall, networking in AWS Fargate provides a flexible and scalable environment for deploying containerized applications, with support for VPC networking, load balancing, service discovery, and security controls.