AWS provides a platform that is ideally suited for building highly available systems, enabling you to build reliable, affordable, fault-tolerant systems that operate with a minimal amount of human interaction. This session covers many of the high-availability and fault-tolerance concepts and features of the various services that you can use to build highly reliable and highly available applications in the AWS Cloud: architectures involving multiple Availability Zones, including EC2 best practices and RDS Multi-AZ deployments; loosely coupled and self-healing systems involving SQS and Auto Scaling; networking best practices for high availability, including Elastic IP addresses, load balancing, and DNS; leveraging services that inherently are built with high-availability and fault tolerance in mind, including S3, Elastic Beanstalk and more.

1. John Hildebrandt
Architecting for High Availability
Solutions Architect, AWS

2. 22
What is High Availability?
• Availability: Percentage of time an application operates during its work
cycle
• Loss of availability is known as an outage or downtime
– App is offline, unreachable, or partially available
– App is slow to use
– Planned and unplanned
• Goal
– No downtime
– Always available

3. 33
Availability is related to
• Scalability
– Ability of an application to accommodate growth without changing design
– If app cannot scale, availability may be impacted
– Scalability doesn’t guarantee availability
• Fault Tolerance
– Built-in redundancy so apps can continue functioning when components fail
– Fault tolerance is crucial to HA
• AWS democratizes High Availability
– Multiple servers, isolated redundant data centers, regions across the globe, FT services, etc.

4. AWS GLOBAL
INFRASTRUCTURE

5. US-WEST (Oregon)
EU-WEST (Ireland)
ASIA PAC (Tokyo)
ASIA PAC
(Singapore)
US-WEST (N. California)
SOUTH AMERICA (Sao Paulo)
US-EAST (Virginia)
AWS GovCloud (US)
ASIA PAC (Sydney)
Regions

6. US-WEST (Oregon))
EU-WEST (Ireland)
ASIA PAC (Tokyo)
ASIA PAC
(Singapore)
US-WEST (N. California)
SOUTH AMERICA (Sao Paulo)
US-EAST (Virginia)
AWS GovCloud (US)
ASIA PAC (Sydney)
Availability Zones

7. AWS BUILDING BLOCKS
Inherently Highly Available and
Fault Tolerant Services
Highly Available with
the right architecture
 Amazon S3
 Amazon DynamoDB
 Amazon CloudFront
 Amazon Route53
 Elastic Load Balancing
 Amazon SQS
 Amazon SNS
 Amazon SES
 Amazon SWF
 …
 Amazon EC2
 Amazon EBS
 Amazon RDS
 Amazon VPC

8. 1. DESIGN FOR FAILURE
2. MULTIPLE AVAILABILITY ZONES
3. SCALING
4. SELF-HEALING
5. LOOSE COUPLING

9. LET’S BUILD A
HIGHLY AVAILABLE
SYSTEM

14. #1
DESIGN FOR FAILURE
●○○○○

15. « Everything fails
all the time »
Werner Vogels
CTO of Amazon

16. AVOID SINGLE POINTS OF FAILURE

17. AVOID SINGLE POINTS OF FAILURE
ASSUME EVERYTHING FAILS,
AND WORK BACKWARDS

18. YOUR GOAL
Applications should continue to function

22. AMAZON EBS
ELASTIC BLOCK STORE

27. AMAZON ELB
ELASTIC LOAD BALANCING

30. HEALTH CHECKS

36. #2
MULTIPLE
AVAILABILITY ZONES
●●○○○

37. AMAZON RDS
MULTI-AZ

42. AMAZON ELB AND
MULTIPLE AZs

45. #3
SCALING
●●●○○

48. AUTO SCALING
SCALE UP/DOWN EC2 CAPACITY

58. #4
SELF-HEALING
●●●●○

59. HEALTH CHECKS
+
AUTO SCALING

64. HEALTH CHECKS
+
AUTO SCALING
=
SELF-HEALING

65. #5
LOOSE
COUPLING
●●●●●

66. BUILD LOOSELY
COUPLED SYSTEMS
The looser they are coupled,
the bigger they scale,
the more fault tolerant they get…

67. AMAZON SQS
SIMPLE QUEUE SERVICE

68. PUBLISH&
NOTIFY
RECEIVE TRANSCODE

69. PUBLISH&
NOTIFY
RECEIVE TRANSCODE

76. VISIBILITY TIMEOUT

84. BUFFERING

91. CLOUDWATCH METRICS
FOR AMAZON SQS
+
AUTO SCALING

98. 1. DESIGN FOR FAILURE
2. MULTIPLE AVAILABILITY ZONES
3. SCALING
4. SELF-HEALING
5. LOOSE COUPLING

99. 1. DESIGN FOR FAILURE
2. MULTIPLE AVAILABILITY ZONES
3. SCALING
4. SELF-HEALING
5. LOOSE COUPLING

100. 1. DESIGN FOR FAILURE
2. MULTIPLE AVAILABILITY ZONES
3. SCALING
4. SELF-HEALING
5. LOOSE COUPLING

101. 1. DESIGN FOR FAILURE
2. MULTIPLE AVAILABILITY ZONES
3. SCALING
4. SELF-HEALING
5. LOOSE COUPLING

102. 1. DESIGN FOR FAILURE
2. MULTIPLE AVAILABILITY ZONES
3. SCALING
4. SELF-HEALING
5. LOOSE COUPLING

103. 1. DESIGN FOR FAILURE
2. MULTIPLE AVAILABILITY ZONES
3. SCALING
4. SELF-HEALING
5. LOOSE COUPLING

104. YOUR GOAL
Applications should continue to function

105. IT’S ALL ABOUT
CHOICE
BALANCE COST & HIGH AVAILABILITY

106. AWS ARCHITECTURE CENTER
http://aws.amazon.com/architecture
AWS TECHNICAL ARTICLES
http://aws.amazon.com/articles
AWS BLOG
http://aws.typepad.com
AWS PODCAST
http://aws.amazon.com/podcast