Day 54 - Networking & Observability

Date: 2025-11-20 (Thursday)
Status: “Planned”


Traffic Paths and Logging

All traffic from LMI functions egresses through the instance ENI in the provider VPC; plan connectivity and monitoring accordingly.

Egress & Destinations

  • Dependency access must route from provider VPC (NAT/Transit/VPC peering/PrivateLink)
  • CloudWatch logs also traverse the instance ENI; allow path to endpoint (public or PrivateLink)

Security Groups

  • No inbound needed; keep SG inbound closed
  • Outbound rules must cover dependencies + CloudWatch

Observability

  • CloudWatch logging remains native; ensure endpoint reachability
  • Monitor instance metrics (EC2 billing, vCPU usage) + Lambda metrics (invokes, errors)

Gotchas

  • Function-level VPC settings are ignored for LMI
  • Instance-level limits (bandwidth/ENI) still apply; size instances accordingly