CONTAINERS in CLOUD FOUNDRY
A container running on a machine is just a process on the host operating system like any other.
The unique part though is in how that process is isolated and restricted in very intentional ways.
What is a STEMCELL ?
A bare minimum OS skeleton with a few common utilities pre-installed
a BOSH Agent, and a few configuration files to securely configure the OS by default.
A stemcell is the OS that runs on the VM (or bare metal)
The concept of a Stemcell solves the following:
capturing a base operating system
versioning changes to the operating system image
reusing base operating system images across VMs of different types
reusing base operating system images across IaaS's of different types
What are BUILDPACKS ?
Buildpacks provide framework and runtime support for your applications.
The Ruby buildpack
has a Ruby interpreter and Rubygems
Knows how to install your application dependencies by processing the Gemfile
What is a
A stack is a prebuilt root filesystem (rootfs) that supports a specific operating system
What is a
A droplet is an archive of
application + buildpack
+ STACK (rootfs)
This is then run with runC
runC is a cli tool for spawning and running containers according to the OCI specification
The level of abstraction is your application
$ cf push application
I am Mick Pollard
Containers in Cloud Foundry
By Mick Pollard