Tips and tricks AWS Solutions Architect Associate #11

ECS

• Fargate: Serverless option; AWS manages infrastructure, you specify RAM/CPU.

• EC2: User manages underlying instances.

Networking & Access

• NLB (Network Load Balancer): High performance, static public IP, supports TCP/UDP.

• NAT Instance: EC2-based; allows private instances to access Internet.

• NAT Gateway: Managed, scalable, must be in public subnet, controlled by NACLs.

• Direct Connect: Dedicated physical link from on-prem to VPC (1/10/100 Gbps).

• Transit Gateway: Hub to interconnect VPCs and VPNs.

• Site-to-Site VPN: On-premises network → VPC.

• PrivateLink: Secure access to services via NLB, multi-tenant friendly.

• VPC Peering: Connects two VPCs; non-transitive.

• VPC Endpoint: Access AWS services privately, without going through Internet.

Load Balancing

• ELB: General load balancer service.

• ALB (Application LB): Layer 7, supports target groups, integrates with WAF.

• Session Distribution: Sticky sessions not ideal with Auto Scaling Groups.

• NLB + ALB: Avoid chaining NLB before ALB; better to use Global Accelerator (GA).

⚡ In short:

• ECS offers choice between Fargate (serverless) and EC2 (user-managed).

• Connectivity options range from NAT/NLB/VPC endpoints to Transit Gateway, VPN, Direct Connect, and PrivateLink.

• Load balancing comes via ALB (L7, smart routing) and NLB (L4, perf/UDP), with GA preferred for global setups