Lee Calcote
Clouds, containers, functions, applications and their management.
From Engines to Orchestrators
Lee Calcote
Sept 30th, 2016
Lee Calcote
clouds, containers, infrastructure, applications
and their management
Show of Hands
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:
- 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
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
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.
Kubernetes
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
Docker Swarm
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
Mesos
+
Marathon
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
-
Summary
A high-level perspective of the container orchestrator spectrum
Lee Calcote
Thank you. Questions?
clouds, containers, infrastructure,
applications and their management
ContainerizeThis 2016: From Engines to Orchestrators
By Lee Calcote
ContainerizeThis 2016: From Engines to Orchestrators
An introduction to container engines (runtimes) and an understanding of when container orchestrators enter and what role they play. We’ll look at what makes each alike, yet unique.
