A Web architect who doesn't usually use Microsoft technologies explains Microsoft's cloud offering, Azure, in terms that hopefully other UNIX/open source people will understand.
8. It’s Magic Fairy Dust You don’t have to worry about the servers! You just deploy your code! You don’t need ops! You don’t need provisioning or monitoring or anything, Azure “does it all for you!” Just right click in Visual Studio and you’re all cloudy! Update your resume!
9. Cold Iron Truth Of course, that’s all BS if you want to do much “real.” But speaking as a open source/Linux/Java sysadmin of 18 years experience who has been known to say “Microsoft is the devil” – Azure is actually pretty good. And it’s even easy to understand, once you dismiss the notion that it’s all “PaaS pixie dust” – it’s more like an IaaS offering with some cool additional facilities. Allow me to explain in sysadmin straight-talk terms. Many of you know AWS so I’ll compare to it some.
10. Azure Compute In your “hosted service,” you define tiers called “roles” instead of individual boxes; you then specify how many “instances” (VMs) run per role. There are three types of roles: Web Role: Win2k8 VM with IIS on it Worker Role: Win2k8 VM without IIS on it VM Role: uploaded Hyper-V VM with Win2k3-8 image of your choice – with some limitations
11. Azure Instance Sizing Extra Small - 1x1 GHz, 768 MB RAM, 20 GB disk, $0.05/instance-hour Small - 1x1.6 GHz, 1.75 GB RAM, 225 GB disk $0.12/instance-hour Medium – 2x1.6 GHz, 3.5 GB RAM, 490 GB disk, $0.24/instance-hour Large – 4x1.6 GHz, 7.0 GB RAM, 1000 GB disk, $0.48/instance-hour Extra Large- 8x1.6 GHz, 14 GB RAM, 2040 GB disk, $0.96/instance-hour Note that these match Amazon EC2 Windows instance specs and costs closely But what about the details, you ask?
12. Role B Count: 2 Update Domains: 2 Fault Domains: 2 Size: Medium Role A Count: 3 Update Domains: 2 Fault Domains: 3 Size: Large www.mycloudapp.net www.mycloudapp.net Load Balancer 10.100.0.36 10.100.0.122 10.100.0.185 Fault Domain 2 Fault Domain 1 Fault Domain 3
13. The Secret Sauce It’s model driven automation from XML config files – see demo The Azure Fabric checks instance health, balances stuff, controls upgrades. You can hook it for events like “RoleChanging”. Managed deployment and upgrades Local compute and storage emulator (that’s a killer feature!) and Visual Studio integration And you can do everything via REST and/or command line!!!
14. Deployment You (or VS) runs cspack.exe which creates a .cspkg package (just a .zip file) and your .cscfgconfig file (just XML) It uploads it to storage and then you can do an in place update (rolling through upgrade domains) or a “VIP swap” of staging to production
15. Demo WARNING! I am not a .NET programmer and use Windows Server only when forced to by software requirements. But I can still do this! If you have deep Microsoft-type questions, though, “I don’t know.” Sorry!
16. Important Lessons - Compute Do not use local instance storage for ANYTHING important. It is ephemeral and role instances may be stopped and started at any time by Azure to move them around. Functional role limitations reduced (running in admin mode, installing using registry, full IIS, startup tasks now allowed) There is a limit of five kinds of role in a hosted service. Use multiple hosted services for complex architectures. Your app’s directory is READ ONLY when deployed/running. Fault domains and upgrade domains are largely Azure managed, you can say “how many upgrade domains.”
17. Azure Storage It’s all REST access, or APIs wrapping REST One “storage account” has a 100 TB limit Blobs – you know, files, like S3. Only one writer at a time but you can make read-only copies. Page blob – optimized for streaming, up to 1 TB Block blob – optimized for random access, up to 200 GB Queues – you can put 8 KB XML messages in them. Drives – a page blob mounted as a NTFS drive
18. More Storage Tables – noSQL style tables, arbitrary fields, partition and row keys for addressing. 1 MB entities with up to 255 properties each. Super scalable. SQL Azure- like SQL Server 2008 in Azure, with limitations of course. 50 GB max database size. No transaction log you can get to.
19. Important Lessons - Storage SQL Azure – no transaction cost, pay by size ($9.99/GB) Azure Tables/Blobs/etc – pay by size ($0.15/GB) and per transaction ($0.01/10k), looking funny at it is a transaction Azure Queues – “you probably don’t want to use them, use SQL Azure.” No guarantees against multiple readers getting the same message. Use a distributed caching midtier for dynamic persistence like memcachedor Velocity (Azure AppFabric cache). Azure Sync the new direction for replication/DR
20. Important Lessons - Networking Under the covers it’s F5 load balancers. Each role has a limit of 5 public or internal “endpoints” (VIPs) you define in the .csdef file. Azure Service Bus allows some pub-sub Azure Connect is a new agent-based VPN node connect option, can connect on premise to Azure… kinda You can Remote Desktop to instances now too You can query the Azure Fabric to get addresses of other instances for peer to peer connection
21. Important Lessons - Operations Azure does not “autoscale.” It will scale, when you insert the integer number of VMs you want. The fabric monitors the instances at a very low level and the “Azure Diagnostics API” just dumps perfmon/log data to storage – it’s up to you to monitor apps and interpret the data (there’s a SCOM plugin for Azure now) Cumulux = RightScale for Azure, look them up
22. Using Azure Right The Azure architecture is specifically optimized for doing things “its way.” “Its way” is luckily arguably the “right way.” Ideally you are writing .NET code that has asynchronous processes (event-driven design) parallelization idempotent operations (handle duplicity) de-normalized, partitioned data (sharding) shared nothing architecture fault-tolerance by redundancy and replication
23. Using Azure Right You can run tomcat, memcached, and mySQL on it – “but you may not want to” You can install more legacy Windows apps now with their newest release – but there are still a lot of limitations, and the cuter your app tries to be with low level stuff, the less likely it’ll work in Azure
24. Why Azure Is Cool To An Old Crusty UNIX Guy The XML config/definition and Azure Fabric – anyone remember PIE? We implemented these concepts for our Amazon apps because they are so necessary. The staging/production VIP swap thing makes for easy continuous integration. Almost everything can be command lined/REST APIed so you can integrate with your existing tools.
25. Azure Resources Make sure and get all the “Azure stuff” – it’s a long and painful list of installs. http://www.microsoft.com/windowsazure/getstarted/ Windows Azure Platform Training Kit is great Azure boot camps - http://www.azurebootcamp.com/ Ryan Dunn’s blog - http://dunnry.com/blog/ Cerebratatools - http://www.cerebrata.com/ Codeplex stuff like Azure Storage Explorer
26. Azure Resources You can get some free Azure in a number of ways – MSDN comes with a minimal entitlement microsoftplatformready.com 30 day pass microsoft.com/bizspark for startups microsoft.com/web/websitespark for web design firms microsoft.com/dreamspark for HS/college students Talk to your Microsoft rep – they offer MTC visits and “TAP/Metro” early access programs