Containers Revealed

Containers Revealed: As Easy as Tic-Tac-Toe @ViscosityNA www.viscosityna.com Latin America
Oracle User Group Community Tour '23 July 29 - August 16, 2023 Sean Scott Oracle ACE Director DoK Community Ambassador Managing Principal Consultant @oraclesean linkedin.com/in/soscott/ [email protected]

DATABASE RELIABILITY ENGINEERING ⁘ DEVOPS & AUTOMATION HIGH AVAILABILITY ⁘
BUSINESS CONTINUITY ⁘ DISASTER RECOVERY MODERNIZATION ⁘ OBSERVABILITY ⁘ ENGINEERED SYSTEMS AutoUpgrade ⁘ Zero Downtime Migrations ⁘ Patching Real Application Clusters ⁘ Data Guard ⁘ Sharding Docker/Containers ⁘ Terraform ⁘ Ansible Exadata ⁘ Oracle Database Appliance AHF ⁘ TFA ⁘ GIMR ⁘ CHA @ViscosityNA www.viscosityna.com Sean Scott Oracle ACE Director DoK Community Ambassador Managing Principal Consultant @oraclesean linkedin.com/in/soscott/ [email protected]

An Open Community for Data on Kubernetes https://dok.community

@ViscosityNA www.viscosityna.com Oracle on Docker Running Oracle Databases in Linux
Containers Download a free sample chapter: https://oraclesean.com 20% Discount Code: OracleDocker https://link.springer.com

@ViscosityNA www.viscosityna.com What Are Containers?

Containers are like lightweight Virtual Machines, right?

@ViscosityNA www.viscosityna.com Three full operating systems Three application/executable directories

@ViscosityNA www.viscosityna.com www.viscosityna.com @ViscosityNA 13 Oracle Databases on a Laptop
2018 MacBook Pro 15", 2.2GHz 6-core Intel Core i7, 16GB, 1TB SSD

@ViscosityNA www.viscosityna.com Virtual Machines: Bootable OS, often heavy Containers: Support
one application or service

@ViscosityNA www.viscosityna.com Virtual Machines: Bootable OS, often heavy A 100-page
book of games & puzzles Containers: Support one application or service A sheet of paper with a Tic-Tac-Toe grid

@ViscosityNA www.viscosityna.com vo • cab • u • lar •
y

@ViscosityNA www.viscosityna.com Stateful Stateless Persistent Immutable Ephemeral Cloud Native Context
Builds Layers Images Services Dockerfile Containers Union Filesystems

@ViscosityNA www.viscosityna.com Games have structured playing surfaces and rules.

@ViscosityNA www.viscosityna.com Services deliver games to players.

@ViscosityNA www.viscosityna.com Images include the game rules and playing surface.

@ViscosityNA www.viscosityna.com Images are a minimal filesystem & metadata needed
to run a service.

@ViscosityNA www.viscosityna.com Running an image starts a Container.

@ViscosityNA www.viscosityna.com A container is: A process on a host,
and; A Union Filesystem.

@ViscosityNA www.viscosityna.com Container processes are isolated.

@ViscosityNA www.viscosityna.com A Union Filesystem has three layers: A Merge
or Union Layer. An Upper Layer. A Lower Layer.

@ViscosityNA www.viscosityna.com A Union Filesystem has three layers: A Merge
or Union Layer: The game. An Upper Layer: The container. A Lower Layer: The image.

@ViscosityNA www.viscosityna.com

@ViscosityNA www.viscosityna.com The Upper (merge) layer isn't "real."

@ViscosityNA www.viscosityna.com The Upper (merge) layer isn't "real." It's a
perceived (calculated) union of: • The game board & rules • Game play

@ViscosityNA www.viscosityna.com Containers persist state (moves) in the run-time layer
of its Union Filesystem. Containers are stateful.

@ViscosityNA www.viscosityna.com Deleting a container removes its Union Filesystem (and
its run-time layer). Containers are Ephemeral

@ViscosityNA www.viscosityna.com Images are immutable and never change.

@ViscosityNA www.viscosityna.com Stalemate!

@ViscosityNA www.viscosityna.com

@ViscosityNA www.viscosityna.com Images are immutable and can't persist state information.
They are stateless.

@ViscosityNA www.viscosityna.com Images = Static Containers = Living

@ViscosityNA www.viscosityna.com Containers are Magic!

@ViscosityNA www.viscosityna.com How much space do three containers use? 500MB 
+ 500MB  + 500MB 500MB 500MB  + 500MB  + 500MB 1,500MB 500MB 500MB 500MB +

@ViscosityNA www.viscosityna.com Multiple identical containers will share an image.

@ViscosityNA www.viscosityna.com Build & Bake Images

@ViscosityNA www.viscosityna.com A Dockerfile is a recipe for building images.

@ViscosityNA www.viscosityna.com Paper Tic-Tac-Toe Grid

@ViscosityNA www.viscosityna.com Image layers are modular and reusable. Layers can
be cached and reused among multiple images.

@ViscosityNA www.viscosityna.com Paper Game of Sums 3x3 Sudoku Tic-Tac-Toe Grid

@ViscosityNA www.viscosityna.com Base Linux OS TensorFlow Flask Python

@ViscosityNA www.viscosityna.com Build Context

@ViscosityNA www.viscosityna.com Context is a pantry of image ingredients.

@ViscosityNA www.viscosityna.com Base Linux OS RU 19.15 RU 19.16 Oracle
Database 19.3.0 RU 19.17 RU 19.18

@ViscosityNA www.viscosityna.com Ignore files limit and control the build context.

@ViscosityNA www.viscosityna.com Images are the minimum collection of files and
directories needed to run an application. They are immutable and stateless.

@ViscosityNA www.viscosityna.com Running an image creates a container as the
upper layer of a union filesystem, superimposed over the image, and starts an isolated process for container activity. Containers are stateful, ephemeral, and persist data to the filesystem.

@ViscosityNA www.viscosityna.com All containers share the same image, allowing them
to achieve tremendous capacity. Containers are efficient and fast because there is nothing to “boot” or copy.

@ViscosityNA www.viscosityna.com Building images creates a layer for each step.
Layers can be cached and shared between images.

@ViscosityNA www.viscosityna.com Images are portable across clouds, operating systems, and
container engines. Images run identically: • in Docker, Podman, Kubernetes, etc.; • on Mac, Windows, or Linux; • and in any Cloud!

@ViscosityNA www.viscosityna.com Contact Me [email protected] https://linktr.ee/oraclesean

Containers Revealed

Containers Revealed

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