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Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist

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Page 1: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

Serverless IoT at iRobot

Ben Kehoe @ben11kehoeCloud Robotics Research Scientist

Page 2: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 2@ben11kehoe

•Cloud Robotics Research Scientist at iRobot

•Serverless evangelist

•AWS Community Hero

About me

Page 3: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 3@ben11kehoe

Page 4: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 4@ben11kehoe

Cloud Robotics:Connecting robots to the internet to help them do more and better things

Page 5: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 5@ben11kehoe

What is serverless?1

iRobot's journey2

Serverless architecture at iRobot3

Serverless deployment at iRobot4

Serverless ops at iRobot5

Serverless organizations6

Page 6: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 6@ben11kehoe

What is serverless?

1

Page 7: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 7@ben11kehoe

•The wrong first question

What is serverless?

Page 8: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 8@ben11kehoe

•Cheaper

•Faster

•Leaner

•Better

What does serverless do?

Page 9: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 9@ben11kehoe

•FaaS

•Event-driven compute

•Never paying for idle

•Containers?

•Public cloud

What serverless is not

Page 10: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 10@ben11kehoe

Increasing serverless-ness with:

•Service-full + emphemeral compute

•Resources billed → resources used

•Smaller, more abstract control plane

Serverless is a spectrum

Page 11: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 11@ben11kehoe

•Cheaper

•Faster

•Leaner

•Better

What does serverless do?

Page 12: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 12@ben11kehoe

On prem IaaS PaaS Serverless

% cost at idle

Cheaper

Not to scale

Page 13: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 13@ben11kehoe

Faster, Leaner

On prem IaaS PaaS Serverless

Effort

Dev Ops DiffOps

On prem IaaS PaaS Serverless

Codebase size

Business logic Other code Infra

Not to scale

Page 14: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 14@ben11kehoe

iRobot's journey

2

Page 15: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 15@ben11kehoe

2015

Page 16: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 16@ben11kehoe

Page 17: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 17@ben11kehoe

Page 18: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 18@ben11kehoe

Page 19: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 19@ben11kehoe

Then

Page 20: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 20@ben11kehoe

Then Now

Page 21: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 21@ben11kehoe

Then Now Future

Page 22: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 22@ben11kehoe

Then Now Future2015

Page 23: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 23@ben11kehoe

AWS IoT

Page 24: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 24@ben11kehoe

•Serverless• Event-driven

• Scalable

• Integrates with AWS ecosystem

•Device shadows

• Integrates with your process

AWS IoT

Page 25: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 25@ben11kehoe

•Event-driven

•Scalable

•Lean for device makers• Reverse: AWS Greengrass

•Focus

IoT + serverlessA natural fit

Page 26: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 26@ben11kehoe

CA Certificate

Robot certificate

signed by CA

Authenticated

MQTT over TLS

AWS IoT

Page 27: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 27@ben11kehoe

HSM

Public key

Signed

certificate

Assembly line

Great Firewall

CA Certificate

Private key

Certificate

AWS IoT

Factory

Page 28: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 28@ben11kehoe

Page 29: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 29@ben11kehoe

•Fully serverless production cloud

•2 million connected robots by 2018

•Mostly serverless analytics platform

•Basis for future data-powered platform

Long story short: success!

Page 30: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 30@ben11kehoe

•Production application:• 100+ Lambda functions

• 25 AWS services

• 0 unmanaged EC2 instances

•AWS footprint:• ~50 accounts, growing constantly

• 1000s of Lambda deploys per day

•Low single digit FTE supporting operations

iRobot scale

Page 31: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 31@ben11kehoe

•Architecture

•Deployment

•Operations

•Organizational

Long story less short

Page 32: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 32@ben11kehoe

Serverless architecture at iRobot

4

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iRobot 2017 | 33@ben11kehoe

def foo(input):

quux = bar(input.baz)

internalState.quux = quux

def bar(input):

# do work

return result

Before serverlessaka the dark ages

EC2

Page 34: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 34@ben11kehoe

def handler(event, context):

quux = Lambda.Invoke(

'bar',

event['baz'])

DynamoDB.PutItem(

'quux',

quux)

def handler(event, context):

# do work

return result

Foo

ExternalState

Bar

DynamoDB

Lambda functions

Page 35: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 35@ben11kehoe

/register Check

Cert

Robots to

Register Queue

Reader

Logging Lifecycle event

PermissionsCreate Shadow

Dead Letter Queue

AWS

IoT

API Gateway

Queues

AWS IoT operations

Page 36: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 36@ben11kehoe

•Call graph → component graph

•Distributed system thinking• Traditionally occurs at system

boundaries

• Serverless: must be treated systematically

•Build robust-by-design systems• Better

Serverless architecture

Page 37: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 40@ben11kehoe

Request IoT topic

Presigned URL

Symmetric

encryption key

Robot

public key

Response IoT topic

Presigned URL

Object encrypted with

symmetric key

HTTPS call

to presigned URL

S3

Key

Management

Service

Robot

certificate

S3

blob store

+

symmetric key

encrypted with

robot public key

Lambda handler

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iRobot 2017 | 43@ben11kehoe

Serverless deployment at iRobot

3

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iRobot 2017 | 44@ben11kehoe

Then Now Future2015

Page 40: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 45@ben11kehoe

Page 41: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 46@ben11kehoe

•Collective noun for cats: "clowder"

•Designated cat herder: CloudFormation

•Custom resource Lambdas• Github repo: iRobotCorporation/cfnlambda

Deployment tool: cloudr

Source

Zipped

functions

S3

blob

store

CFN

template

CFN

stack

Custom

resource

Lambda

Page 42: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 47@ben11kehoe

Red/Black deployments

Page 43: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 48@ben11kehoe

•Serverless = no overhead to red/back

• IoT makes things tricky

•Data stores, etc. have separate life cycle

Hosting multiple versions

Page 44: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 49@ben11kehoe

Deployed system architecture

Application Proxy resources Resources

v1

v2

v3

v4

A1 B1

C1

B2

D1

A1 B1

C1

B2A1

C1

D1

A1

C1

B2

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iRobot 2017 | 53@ben11kehoe

Serverless operations at iRobot

5

Page 46: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 54@ben11kehoe

• Sumo Logic

• Essential for log sleuthing

• Get all data associated with an artifact immediately across all accounts

• Provides quantitative metrics on fleet health

• Alarms and notifications

• Extensive use of CloudWatch as well

Monitoring

Page 47: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 58@ben11kehoe

• Same environment in the platform as production

• Orders of magnitude more churn• Exercises the account limits• Tests metrics to determine relevance and

meaning

• Bonus – Developer activity provides additional visibility into how the platform is currently behaving• Higher volume of deployments in many

different AWS accounts means problems found quickly

• This can alert us prior to problems hitting prod

DevOpsDevelopers can be platform testers, canaries, and guinea pigs

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iRobot 2017 | 59@ben11kehoe

Metrics are our portal : Example – AWS IoT• AWS IoT today has a ton of metrics

• At launch, it had <10

• Without throttling metrics, thing shadow updates, or WebSocketmetrics it was hard to debug issues• Especially early on with small numbers

of robots

• Can I connect? How many publishes?

• Load scale, are we over our limits?

Visibility

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iRobot 2017 | 60@ben11kehoe

• Enterprise Support has been a valuable resource• They are our eyes and ears within AWS

• Engage with them to run load tests, understand account limits

• Our AWS Support team has made the effort to understand our technology choices

• All of our AWS users, company-wide, benefit from being able to create tickets

AWS Enterprise Support

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iRobot 2017 | 61@ben11kehoe

• Metrics, metrics, metrics• Service teams are always on the lookout

for which new metrics to include – connect with them and share your requests!

• Kinesis shard-level metrics, Lambda iterator ages, all added with user input and makes a real difference in understanding system performance

• Personal Health Dashboard• Per-account service health means AWS

can update those affected customers more directly

• When performance is degraded, status is important for ops to show evidence that it isn’t a problem with our software

The future of improved AWS visibilityLooking toward the horizon

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iRobot 2017 | 62@ben11kehoe

Serverless organizations

6

Page 52: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 63@ben11kehoe

•Heed the warning

• Information flow is different in serverless architecture

•Organization must change for architecture to succeed

Conway's Law

https://commons.wikimedia.org/wiki/File:Gospers_glider_gun.gif

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iRobot 2017 | 64@ben11kehoe

•Servers → serverless is like on-prem → cloud

•Easier overall and in most respects• But also includes new challenges

•Outsourcing doesn’t mean you do zero work

•Being clear about this organizationally is critical

DiffOps

Page 54: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 65@ben11kehoe

•No provider is immune to problems

•Small effects are more common than big outages

•More services = blips could be encountered more frequently

•This comes with the territory• Set expectations internally

• Architecting robustly is key

The cloud has weather

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iRobot 2017 | 66@ben11kehoe

• You only know what the provider tells you• Architecture• Security• Operations

• How do they actually do all of the stuff they do?

• Many known unknowns and unknown unknowns

• Unknown unknown unknowns: what you don’t know that they don’t know they don’t know

Visibility

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iRobot 2017 | 67@ben11kehoe

•First: gather data

•Root cause: our code or platform?

•Own the impact to your customers

•Diagnose your applications' handling of incident• Live and postmortem

•Aftermath

Reacting to incidents

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iRobot 2017 | 68@ben11kehoe

Summing up

7

Page 58: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 69@ben11kehoe

Serverless is:

•Cheaper

•Faster

•Leaner

•Better

Serverless

Serverless-ness goes with:

•Service-full + emphemeral compute

•Resources billed → resources used

•Smaller, more abstract control plane

Page 59: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 70@ben11kehoe

•Successfully transitioned from turnkey to application built on public cloud

•Skipped learning to build elastic cloud infrastructure

•Fully serverless production application

Serverless at iRobot

Page 60: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 71@ben11kehoe

•Serverless deployment is still not a solved problem

•Call graph → component graph

•Visibility is the biggest operations obstacle

Lessons learned

Page 61: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

iRobot 2017 | 72@ben11kehoe

•Conway's Law

•Cloud has weather

•Set expectations

•Focus on TCO

Serverless organizations

Page 62: Serverless IoT at iRobot - QCon San Francisco · 2020-06-05 · Serverless IoT at iRobot Ben Kehoe @ben11kehoe Cloud Robotics Research Scientist. ... Serverless Serverless-ness goes

Questions?