Assume that we have got an exe(unmanaged/managed) which is crashing/hang/wanted to debug and see the intermediate values etc. For this example, I have used the below simple cpp program compiled to exe.
Steps for debugging this complied exe in Windbg:
1) Launch Windbg, -> Open Executable, browse and select our cpp program output “ConsoleApplication1.exe”
2) Now set the symbol path and source path pointing to its corresponding directory.
3) Reload the symbol to make sure the relevant symbols loaded.
4) If you press “g” mean go/F5 would run the program and displays the output.
5) Let us put some breakpoints at Main method and also Swap2Numbers to step in line by line debugging.
6) Since we have mapped the source code path also, now on typing “t” would execute/step in line by line. You would also notice the source code window opened up and breakpoint indicator set.
7) If you wanted to unassemble, then use> uf ConsoleApplication1!main (assembly code).
8) When you go line by line debugging, you can view the intermediate value of the function by typing >dv (display variable)
While I was going through the Exam: 70-532 preparation material, I hit these following pattern useful to the Availability, Resiliency and Scalability(ASR) of Azure WebSites and Azure Cloud Services. Wanted to table out here for later reference and detailed reading.
Useful for WebSites/WebJobs & WebRole/WorkerRole
■■ Static Content Hosting pattern
■■ Cache-Aside pattern
■■ Health Endpoint Monitoring pattern
■■ Compensating Transaction pattern
■■ Command and Query Responsibility Segregation pattern(CQRS)
Useful for WebJobs and WorkerRole
■■ Competing Consumers pattern
■■ Priority Queue pattern
■■ Queue-Based Load Leveling pattern
■■ Leader Election pattern
■■ Scheduler Agent Supervisor pattern
RESILIENT CLOUD ARCHITECTURES
> Microsoft Patterns & Practices at http://msdn.microsoft.com/en-us/library/dn568099.aspx [Download PDF]
> Designing resilient architectures for the cloud: http://msdn.microsoft.com/library/azure/jj853352.aspx [provides additinal insight, some specific to Cloud]
I just saw scott post on Azure Resource API lib intro. I thought let me think over all possible ways(recollect) today used to manage Azure Resources like VM, Websites, jobs etc from ones desktop.
1) https://portal.azure.com – famously called azure preview portal.
2) https://manage.windowsazure.com – old portal or manage azure portal.
3) Azure PowerShell – PowerShell is a friendly tool for infra guys/DevOps/Admin who manages and automate stuffs using PS commandlets, or advanced stuff like DSC -Desired State configuration, puppet,chef etc.
> There are lot of infra tools available in market place.
4) Azure Resource Manager API – over REST API – fire commands like PUT,GET,POST from your browser. You could also use ARM client here. It is really nice cmd utility with simple commands written by David E
5) Microsoft Azure Cross Platform Command Line (separate installer available for Mac and windows) – azure-xplat-cli
6) From your managed .NET code too – Microsoft Azure Management Libraries 2.0.0
> Scott H explained how one could do this coding here
7) Using Visual Studio Server Explorer – explained here.
P.s: Let me know if you have any comments regarding this and any other ways left out.
When we swap deployment slots, all of the website content is swapped, but the not the configuration.
The following configuration items will move to the destination slot:
■■ General settings (for example, .NET framework version, Web Sockets, Always On)
■■ Connection strings
■■ Handler mappings
■■ Application and site diagnostics settings
■■ Monitoring settings
The following configuration items will not move to the destination slot:
■■ Publishing endpoints
■■ Custom domain names
■■ SSL certificates and bindings
■■ Scale settings
Note: this means that settings such as your db connectiong strings should be configured with the prod values before swapping.
Last week I have cleared my 70-487 Developing Microsoft Azure and Web Services certification. I have started preparing for 45+ days on and off, mostly weekend reading and able to clear through second shot offer. There are plenty of materials there to prepare, but I urge to stick with official curriculum + MVA (microsoft virtual academy videos) for this exam. I had internal employee measure up account with some sample questions, with deep understanding of all those concepts + small hands on helped me crack it. Here is what you will learn through this certification,
Chapter 1) Accessing Data using – EF, WCF DataServices, Azure Data Storage, Transaction, Caching, XML ds (data). ..
Chapter 2) Querying and Manipulating data by using EF – LINQ to Objects, entities, ADO.NET, EF, Lazy loading,data model…
Chapter 3) Designing and implementing WCF Services – SOA concepts, WCF API obj and config, Securing, consuming, version, Azure Service bus, one way-two way, hosting..
Chapter 4) Create and consume Web API based services – Design a web api, implement, secure, host and consume web api web services
Chapter 5): Deploying web application and Services- Design, deployment strategy, Configure, manage packages using Nuget, create, configure and publish a web package, share assemblies.
Overall, we will learn back-end programming/db programming + infra projecs like publishing, nuget, etc also helps us to uinderstand end -to end.
Study notes from Chris – http://www.bloggedbychris.com/2013/01/24/microsoft-exam-70-487-study-notes/
DebugView is a developer friendly tool helps you to monitor debug output messages from local or nw system – from managed/unmanaged code. Recently I was debugging managed COM dll created in C# consumed in office application. I wanted a tool to debug end to end, Let say, your Office files VBA macro calls .NET COM dll for processing some complex logic and then returns the value to your macro.
In dev environment, we usually attach VS to the application and debug them, in VBA using debug.print statements. Assume that, you don’t have VS at your production server or customer machine where you wanted to debug them badly. Here is where debugview comes for rescue.
System.Diagnostics.Debug.WriteLine("This is from .NET before word instance.");
Private Declare Sub OutputDebugString Lib "kernel32" Alias "OutputDebugStringA" (ByVal lpOutputString As String)
Private Sub DebugPrint(dbgOutput As String)
DebugPrint ("Test message for the debugger")
Note: Make sue you run as “Admin”.
A Cloud and Azure Glossary for the Confused
Windows Azure Platform Glossary for IT Pros
Microsoft Patterns and practices – Azure Glossary
Pushing the Limits of Windows: Physical Memory
Pushing the Limits of Windows: Virtual Memory
Pushing the Limits of Windows: Paged and Nonpaged Pool
This weekend I had a chance to try this blog post by Kirk Evans here. Finally decided to try myself and experience the fact. Trust me, its one of the cool feature implemented in Azure. I can’t imagine how many lines of code would execute in the back-end for each of those button click from portal, say increase the core, queue, cpu etc – really hard to imagine or think about it.
#Hats off to Azure team for their flawless implementation. I was able to experience this feature end to end without any bug or hassle. few observation from my point,
How to automatically scale the worker role based on the number of messages in a queue
+ Kirk has used Azure service bus to validate this functionality. I have also used the same .NET console application to pump the queue message. It took sometime to fix those project reference etc. Finally with Nuget able to resolve the dependencies and publish it successfully.
+ Everything went flawlessly from there. Spent my time mostly in the portal to know the settings and tweaking it. I think we should bring those nuget console to the project context menu for quicker launch. Right now it is buried some where under main menu of Visual Studio.
+ Though auto scaling worked like charm, the dashboard chart is not getting refreshed or reflecting real data, not sure what’s going on there.
Note: Auto scale feature automatically creates or destroys the VM’s based on the rules
+ Screenshots here.
Happy weekend !
I’ve just come across the below Pizza as a Service chart from linkedin. I just added our Azure chart as well below for side by side comparison. I should give full credit to “Albert Barron” who created this pizza chart and article here. Very layman explanation for Cloud service.. Fantastic.
This weekend, I had a chance to explore Azure RemoteApp. In nutshell, this App runs on Windows 2012 R2 over rdp service. We usually RDP to a remote machine but in this case, we are rdp’ing to a particular published apps without any visible difference like window border or floating bar etc. Trust me, end user won’t be able to identify whether they are on a remote app or local app. I am really impressed with the design thought.
We can connect to a remotely published apps from a azure portal and then use it by installaing a small exe at client machine for logon and app selection. As of now, It comes with few default Office applications(apps) but in case of hybrid option you can customize by uploading your VHD’s as per our wish.
Since this supports resume and continue kind of state management, you could logoff from your office and then continue from home using any device from the place where you’ve left.
+ It delivers the functionality of the on-premises Microsoft RemoteApp, backed by Remote Desktop Services
+ Helps you provide secure, remote access to applications from many different user devices. Available for Windows 8.1, Windows 8, Windows 7 Service Pack 1, iOS, Mac OS X, Windows RT, Android, devices, and Windows Phone. It also support the Windows 10 preview.
> To achieve this, you need to install a clickonce installable RemoteAppClient from here – https://www.remoteapp.windowsazure.com/ClientDownload/Windows.aspx
> Azure documentation: http://azure.microsoft.com/en-us/documentation/services/remoteapp/
> Azure RemoteApp Cloud Deployment overview
> Understanding Azure Remote App
Microsoft Azure infographics
Microsoft Architecture Blueprints
Top architecture trends and perspectives
Cloud application development
I got this tools link while searching for Azure Storage free tools – explorer. Azure Storage Explorer is simply a nice tool to work and explore. It is free, elegant and clutter free to use. It just fulfill our expectation. #Good job by david
Download it from here – http://azurestorageexplorer.codeplex.com/
While working with Azure storage, I ran into a tricky problem where I could not able to delete the storage created implicitly during VM creation.
Though I deleted all my VM’s from my account but these underlying storage were listed under my account for some reason. I tried hard to get rid of this by going through all the dependencies but no luck.
I tried deleting using Azure Storage Explorer but same problem persisted.
Resolution: You have to delete VHD files before deleting storage. When Virtual Machine is removed, VHD file exists there for some reason – may be by design think so. You can delete it from Virtual Machines -> Disks and then try deleting the storage.
My reading notes from this book which I bought recently – Developing Cloud Applications with Windows Azure Storage by Paul Mehner.
I will try simplify the content with examples for quicker references. Hope you enjoy this series about Windows Azure Storage.
+ Windows Azure Storage(WAS) – provides independent data management services to our application – data storage for any application/any platform/any language over HTTP
+ We are moving to NoSQL era due to volume of data/performance. In 1970’s we started with flat file –> file based relational db’s -> Relational -> Hierarchical -> N/w -> Federated -> NoSQL (not only SQL).
+ WAS is implements as NoSQL-styled db.
+ There are 3 high level data types in WAS – Blob, Tables and Queues.
+ WAS is not a relational db
+ Access to this WAS is done with simple REST API
+ WAS supports scalability, replication, geo-locaiton, geo-replication, independent and interoperability, maintains fully consistent model (Amazon S3 is eventually consitent model – read operation after update may/may not return the very recent updated data)
BLOBS (for storing unstructured data – doc, pictures, videos and music)
> Windows Azure blob service provides a simple RESTful APi for storing and retrieving unstructured data.
> Blobs are organized into Containers(similar to directories), you can have any number of blob’s under containers.
> Blobs and blob containers are easily accessible with unique url’s.
> You can set public access as well.
> Ideal for the storage of web content
> Windows Azure Table service provides a simple RESTful Api for storing massive amounts of semi structured data.
> These tables are not at all like relational db tables.
> Rows are called entities, consist of properties, which are like columns.
> Different rows stored in the same table can often have different set of properties.
> Queues do not provide permanent storage of the message they handle.
> Unprocessed messages will be deleted from the queue after 7 days.
> Same like MSMQ, it will get deleted upon read, exposed through RESTful API’s.
Microsoft Azure is growing faster than ever. Being developer for all these years, I have not considered Azure is for Developer. Trust me, you will be bowled after seeing whole list of Azure offerings.
In future, there is no surprise that every developer would be touching atleast one of their offerings at some point in their dev time. If you are Microsoft. NET dev, then there is high chance that you would be asked to consider Azure offerings in your proposal/delivery. This year I am going to concentrate on Microsoft Azure and its bread crumb of technologies from Developer perspective.
Let start with simple web applications hosting, today you can do it in 3 ways using Azure services.
1) Using Azure VM – host under dedicated IIS(VM) – PaaS
> on par with your on-Premises deployments
> you own the VM(your box), so you need to take care of OS updates
> you manage the hostnames inside IIS (setup the host header within IIS)
> pretty much you can install/manage as like your on-premise edition
2) Using Cloud Services- host using Web Role(WR) -IaaS
> you own only a web-role, could service save us from OS updates and other headaches.
> You own the application, you could RDP’s to this VM and perform as you do in your on-premise
> one thing to remember – these are stateless VM. Every start and stop you get a different VM
> you own the code and your application updates – rest is taken care by MS.
> well suited for multitier application – can be scaled independetly (web and work roles)
3) Host it as Azure Website(AWs)
> easiest way to host the websites
> don’t have to worry about OS updates
> all your application updates are pushed through your tfs/dropbox.
> one click swap to production vs staging slots and other cool features
> web jobs adds processing power to our websites by adding worker role to your existing cloud services
> well suited for hosting sites like – wordpress, joomla, drupal- .NET, Java, PHP, Node.js, Python
> built-in Autoscale and load balancing
> high availability and auto-patching
> continous deployment with Git, TFS, GitHub
> SQL Db, Mysql, DocumentDB, Search, MongoDB
Let me start explore from db side in our next post :)