From Engines to Orchestrators

http://calcotestudios.com/feto

http://calcotestudios.com/feto

Lee Calcote
Sept 30th, 2016

Lee Calcote

clouds, containers, infrastructure, applications

and their management

linkedin.com/in/leecalcote

@lcalcote

blog.gingergeek.com

lee@calcotestudios.com

Show of Hands

@lcalcote

Types of Containers

System Containers

Like a VM
Full OS image
Multiple processes

Application Containers

Single process

Use namespaces to deal with resource isolation for a single process.
Use cgroups to manage resources for a group of processes.

Similarities:

@lcalcote

rkt
docker
runC
kurma

---

containerd
systemd-nspawn

OpenVZ
Solaris Zones
BSD jails
Linux-VServer
AIX WPARs
LXC

----

LXD
CGManager
machinectl

----

qemu-kvm, lkvm

System Container Engines

Application Container Engines

Container Specifications

@lcalcote

Implemented by -

rkt is the canonical implementation
Kurma leverages runC
Jetpack is an implementation of for FreeBSD using jails and ZFS

Implemented by -

runC is the reference implementation
runV is a hypervisor-based runtime
cc-oci-runtime launches an Intel VT-x secured Clear Containers 2.0 hypervisor

@lcalcote

runtime-spec
- a specification for the lifecycle of a running container
runtime-tools
- tooling for the runtime

image-spec
- a software shipping container image format spec with security and naming as components
image-tools
- tooling for the image

https://opencontainers.org

Get Started with your Engines

and get your engines started

Popular Engine
process models

rkt executes as CLI; no daemon
Can run Docker Images and also App Container Images (ACIs)
Security has been a focal concern
uses HTTPS to locate and download remote ACIs and their attached signatures

Docker Engine runs a daemon

rkt

systemd

$ rkt run postgres

application

systemd

$ docker run postgres

application

Docker Engine

containerd

runC

Definition:

[ awr -k uh -streyt -or]

[k uh n- tey-ner]

Core
Capabilities

Cluster Management
- Host Discovery
- Host Health Monitoring
Scheduling
Orchestrator Updates and Host Maintenance
Service Discovery
Networking and Load-Balancing

Additional
Key Capabilities

Application Health Monitoring
Application Deployments
Application Performance Monitoring

One size does not fit all.

A strict apples-to-apples comparison is inappropriate and not the objective, hence characterizing and contrasting.

@lcalcote

Kubernetes

@lcalcote

Genesis & Purpose

an opinionated framework for building distributed systems
- or as its tagline states "an open source system for automating deployment, scaling, and operations of applications."
Written in Golang, Kubernetes is lightweight, modular and extensible
considered a third generation container orchestrator led by Google, Red Hat and others.
- bakes in load-balancing, scale, volumes, deployments, secret management and cross-cluster federated services among other features.
Declaratively, opinionated with many key features included

@lcalcote

Docker Swarm

@lcalcote

Genesis & Purpose

Swarm is simple and easy to setup.
Swarm is responsible for the clustering and scheduling aspects of orchestration.
Originally an imperative system, now declarative
Swarm’s architecture is not complex as those of Kubernetes and Mesos
Written in Golang, Swarm is lightweight, modular and extensible

@lcalcote

Mesos

+

Marathon

@lcalcote

Genesis & Purpose

Mesos is a distributed systems kernel
- stitches together many different machines into a logical computer
Mesos has been around the longest (launched in 2009)
- and is arguably the most stable, with highest (proven) scale currently
Mesos is written in C++
- with Java, Python and C++ APIs
Marathon as a Framework
- Marathon is one of a number of frameworks (Chronos and Aurora other examples) that may be run on top of Mesos
- Frameworks have a scheduler and executor. Schedulers get resource offers. Executors run tasks.
- Marathon is written in Scala