Docker Containers OTA for IoT Gateways

Shashank Jain/ SAP HCP

Customer

About Me

• Development Architect @SAP Bangalore

• Cloud Enthusiast

• Email : shashank.jain01@sap.com

• Twitter : @smjain

Customer

Motivation

• IoT Device Explosion

• Container Boom

• Using Developer Workflows like Heroku and Other PaaS for IoT

• A Gateway Centric Solution to Merge Both Worlds

Customer

Docker Docker Everywhere

Customer

What is Docker?

• Docker is a tool created by the folks at dotCloud to make using Linux Containers (LXC) easier to use.

• Linux Containers are basically light weight Virtual Machines (VM). A Linux container runs Unix processes with strong guarantees of isolation across servers.

• Your software runs repeatedly everywhere because its Container includes all of its dependencies

Customer

Docker Architecture

Customer

Docker File System

Customer

Docker vs VMs

Size:

VMs are very large which makes them impractical to store and transfer.

VM: You have a container image that is 1GB in size. If you wanted to use a Full VM, you would need to have 1GB times x number of VMs you want.

Docker: With LXC you can share the bulk of the 1GB. It means that If you have 1000 containers you still might only have a little over 1GB of space for the containers OS, assuming they are all running the same OS image.

Customer

Docker vs VMs

Performance:

VM: A full virtualized system usually takes minutes to start.

Docker: LXC containers take seconds, and most times less then a second.

Customer

Docker Advantage

Throwable Sandboxes: Create a container in a minute to test your stuffs and tear it

down.

Fine Application Delivery: Containers allow you to package just about any application.

You could add the dependencies of the application in the container itself. Ex: MySQL

service.

Reusability: Docker makes containers reusable.

Uniformity: Development and production Environments

Customer

Some Terminologies on Docker

Image

An image is a read only layer used to build a container. They do not change.

* Container

Is basically a self contained runtime environment that is built using one or more images.

You can commit your changes to a container and create an image.

* Docker index / registry

These are public or private servers where people can upload their repositories so they

can easily share what they made.

Customer

Docker Under The Hoods Lets see what docker is doing here.

1. Downloaded the image from docker repo

2. Generated a new LXC container

3. Created a new file system

4. Mounted a read/write layer

5. Allocated network interface

6. Setup IP

7. Setup NATting

8 Executed the bash shell in the container

Customer

SAP IoT Architecture

Customer

SAP IoT Architecture

Control Plane

• Sets up the Rules and Data flows

• Currently uses the Camel Routes as the mechanism

Data Plane

• Responsible for Using the rules/flows and sending data upstream to the Cloud

Customer

IoT Gateway/Connector

In general the IoT Connector should exhibit the following properties

• The connector should have the capability to support variety of protocols out of the box and also the

capability to easily introduce adapters for enabling communication via new/custom protocols.

• The connector should allow easy pluggabilty of modules like filtering/Edge Stream Processing

(majorly on the fly) , into the existing runtime

• The connector should allow if needed a store and forward mechanism for Guaranteed delivery

• The connector should have proper failure handling primitives built in.

• The connector should allow proper usage of the hardware and implement a capability to apply back

pressure to allow bounded latency and prevent abrupt crashing of the runtime due to resource

exhaustion.

Customer

IoT Gateway Data Pipeline

Customer

Currency of Deployment For Gateways

Yesterday

OSGi Components

Advantages

• Lifecycle managed by OSGi

• Easy to introduce new component in runtime

Challenges

• Limited Flexibility in defining Flows

• Coupled to Specific Technologies

Customer

Currency of Deployment For Gateways

Today

Camel Routes orchestrating OSGi components

Advantages

• Ability to define new Data flows/Routes on the fly

• Can run multiple data flows on a single gateway

Challenges Coupled to Specific Set of Technologies like Java/Camel, Choice of DB

Customer

Currency of Deployment For Gateways

Future

Docker Images

Advantages

• Deploy the complete pipeline instead of Components

• Immutability Rules

Challenges

• Deploying Images on low ended machines

Customer

Docker OTA For IoT Gateways Opportunity

• Reduce overall deployment downtime for IoT landscapes.

• Achieve an immutable deployment strategy using containers.

• Increase support driven development

• Allow polyglot development based on skills of development teams.

Customer

Rationale • The heterogeneous nature of IoT Services demands for stronger CI

capabilities

• Current CI landscapes work as follows

• The subsystems, subcomponents, and services that are interconnected are owned by different groups and third party vendors. Inability to upgrade online, just one dependent subcomponent could impact the whole application.

• Considerable effort and coordination among different teams is needed to set the right configuration data populated across all the systems/ devices.

Customer

PROPOSED FLOW

Customer

Benefits

By Introducing Immutability we can do

Canary Deployments

• Apply changes to a selected fleet of Gateways

• If All works well, Apply the changes to all the gateways

• If there are issues we can rollback to the last know good image.

Customer

Challenges

• Adapters are customer Specific.

• The protocols are propertiery and native at times.

• Some protocols cant be shared and have IP around them.

Customer

Possible Solutions Break the solution into 3 parts

1. A Customer specific Adapter Image

2. A Extended image

3. Bind the images via zeromq

This allows

1. Customer to write adapter in Language of their choice

2. SAP to write the rest of data pipeline in the language/framework they want

Customer

Flow

Customer

Current Status

Working on a Prototype for the above flow

• Using 2 runtimes

1. Java based Data Pipeline

2. Golang Based Data Pipeline

• Should have the ability to switch via a click.

Customer