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APRIL 17, 2012 | SLIDE 1

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Architectural Patterns for the Cloud
Maarten Balliauw
@maartenballiauw
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3.
Who am I?
 Maarten Balliauw
 Antwerp, Belgium
 www.realdolmen.com
 Focus on web
 ASP.NET MVC, Windows Azure, SignalR, ...
 MVP Windows Azure & ASPInsider
 http://blog.maartenballiauw.be
 @maartenballiauw
 Author: Pro NuGet - http://amzn.to/pronuget
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4.
Agenda
 Quick recap: Windows Azure
 What’s different in the cloud?
 Rethinking apps
 Conclusion
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5.
Quick recap
Windows Azure
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Windows Azure is a cloud platform
 On-demand
 Self-service
 Pay per use
 Highly automated
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Windows Azure Components
Compute Storage SQL Azure Service Bus Connect
BI Marketplace CDN Caching ACS
Application Services Storage Services Foundation Services
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What’s different
in the cloud?
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Differences with your infrastructure
 Uniform
 Automated
 Designed for failure
 Designed for scale
 It’s not in your datacenter
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Uniform
 Every machine +/- the same
 No specialized hardware
 No specialized OS*
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Demo
Customizing the Windows Azure virtual machine
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Automated
 Makes decisions on provisioning &
updating
 Monitors health
 The platform knows what’s best
 Not necessarily for your app…
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Designed for failure
UD 1
UD 2
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Designed for scale
 Scale out
 Stateless
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It’s not in your datacenter
 Integration
 Authentication
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Rethinking apps
What do I have to think about?
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Scenario: Newspaper website
 National & International
 Sudden spikes in usage
 Dynamic content
 Static content
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Current architecture
 Will work on the cloud!
 Will fail on the cloud!
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Design for failure
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Assume everything will fail
 Automated service maintenance
 Compute node crash
 Storage throttling
 SQL Azure throttling
 Connectivity
 Your code
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21.
Retry everything
SQL Azure Error 40501
The service is currently busy. Retry the
request after 10 seconds.
Retry against anything that might be external
SQL Azure, Windows Azure Storage, Service Bus, …
http://windowsazurecat.com/2011/02/transient-fault-
handling-framework/
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The entire datacenter fails!
 Run in 2+ datacenters
 Keep data synchronized
 All data
 or limit scope
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23.
Refactoring the architecture
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Windows Azure Data Centers
100ms
50ms
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Windows Azure Traffic Manager
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Windows Azure Traffic Manager
 Strategies
 Round-robin
 Fail-over
 Performance (geo)
 Solves datacenter outage
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Are we there yet?
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Solutions to a SPOF being down
 Set a monitoring endpoint for TM
 Take the entire datacenter out of the loop
 Take the SPOF out of the story
 Degrade gracefully
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Refactoring our architecture
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Design for scale
*and failure
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Belgians are not used to snow
What will happen to our
architecture?
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Here’s what will happen…
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Solution: scale out!
 Add more VM’s!
 Autoscaling (WASABi)
 Windows Azure Autoscaling Application Block
 Enterprise Library
 http://entlib.codeplex.com/wikipage?title=WASABiBet
aReleaseNotes&referringTitle=EntLib5Azure
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Solution: scale out!
 Add more VM’s!
 Autoscaling (as-a-Service)
 www.opstera.com
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Here’s what will happen…
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SQL Azure
 Monitored by the platform
 The platform does not like high DB traffic
 Throttling & retries
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Caching
 Most of our users are doing reads
 Cache content near where it’s needed
 Windows Azure Caching
 Blob Storage
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Refactoring our architecture
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Caching
 How do you populate it?
 When do you populate it?
 When do you invalidate it?
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Work asynchrounously
 Read from cache
 Present? Use cache
 Not present? Ask to cache it & read from
DB
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Refactoring our architecture
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A typical web request…
 1 request is dynamic
 493 requests are static*
 Get that static content out of your servers!
 Cache content near where it’s needed
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Windows Azure CDN
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Refactoring our architecture
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Conclusion
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Key takeaways
 Cloud is different
 Design for failure
 Design for scale
 Work asynchronously
 Cache close to where it’s needed
 Also think price vs. Allowed outage
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47.
One more… Learn from others!
 Amazon - http://slidesha.re/AlaHIG
 Trello - http://bit.ly/xO5G9e
 YouPorn - http://bit.ly/yUSanQ
 StackOverflow - http://bit.ly/xkLvH9
 InstaGram - http://bit.ly/xbWuzx
 … (highscalability.com)
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48.
http://blog.maartenballiauw.be
@maartenballiauw
http://amzn.to/pronuget
or Install-Package ProNuGet
THANK YOU!
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