Basic Info

WHY ?

Current Infra

Docker Swarm as the orchestration engine

Pros:

• Solves lots of issues, like container lifetime and ease of deployment(up to a point)

• Simple to setup

• Less complicated (comparatively)

Cons:

• Ops at scale is hard ( like swarm reset, network issues)

• At scale it doesn't have the knobs to control the infra nuances unto our liking

• Autoscaling or other cloud-native goodies are absent

• No way to get realtime telemetry or metrics about the state of infra (especially service communication)

• No platforms like knative or istio, which is an instant value add-on for both/infra and addon

Open

Container Fundamentals

• VM vs Container

• Key concepts of container

  • Containers are applications which is restricted by kernel feature called namespaces

    • pid - Process Namespace

    • net - Network

    • mnt - FileSystem

    • usr - UserID

    • utc - hostname

    • ipc - semaphores, channels

  • Cgroups will limit the resource usage

    • ResouceUsage

      • Memory

      • CPU

      • Block I/O

      • Network

    • Device Node access control

      • /dev/*

• Docker is an engine which makes such containers. There are alternatives like containerd, rkt etc