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Monday, 19 December 2016

How to auto-heal your web app so you hopefully get your weekends back

Summary

This document outlines how to set up auto-healing for your web app. At times you may be enjoying your weekend and get a call telling you an app is constantly running at 100% CPU. 
Autoheal is a way to automatically recycle your app pool based on certain triggers.
I have created a POC web app with 3 instance VMs.I have turned on all diagnostic logs and set them to verbose. 
Here is the Event Log before enabling auto-heal in the web.config (there were more records but I removed them as they were all similar):














And here is the new web.config. This will recycle the app pool when we get 20 or more requests in a period of 30 seconds:










So, once this is deployed, I will call the end point 100 times in less than 30 seconds which should cause the trigger to run its action - Recycle
Here is the calling Powershell code (this just simulates a client):

$URL = 'http://autohealingpoc.azurewebsites.net/api/values';

$contentType = "application/json";
for($i=1
    $i -le 100
    $i++){   
    Write-Host 'I is: ' + $i;
   $response = Invoke-RestMethod -Method Get -Uri $URL -Headers $headers -ContentType $contentType;
   $response;
}

After I ran 100 requests in less than 30 seconds you can see in the event log that the instance RD0003FF857039 recycled:











When I really loaded it up, all 3 instance auto-healed:






















Thanks
Russ

Monday, 28 November 2016

Monitor your Azure API Management Instance with PowerBI

Monitor your Azure API Management Instance with PowerBI

Summary

This document outlines the steps involved to monitor your Azure API management instance with PowerBI.

Note: I will refer to Azure API management as APIM in this document.

Steps will include:

  • Add a logger, using the APIM REST API, to your APIM instance to send events to an event hub
  • Set up a Stream Analytics job - It consists of one or more input data sources, a query expressing the data transformation, and one or more output targets that results are written to. Together these enable the user to perform data analytics processing for streaming data scenarios
  • Build a PowerBI dashboard to see your APIM data in a format that suits your business requirements.

Adding a logger to APIM

First thing you need to do is add a logger to your APIM instance using the APIM REST API. I will use Postman to do this.

Firstly, in your APIM instance, enable the REST API:















Secondly, go to the bottom of the security page where you enabled the REST API and generate a shared access key:



















You will use this later in Postman after we first create an Azure Event hub.

Create an Event Hub

Go into your Azure portal and create an event hub.





Ensure you create to Event Hub shared access policies. 1 for sending to the event hub and 1 for receiving. This is to allow you more granular control over your hub.







































Creating the logger in Postman

Now that you have an Event Hub, the next step is to configure a Logger in your API Management service so that it can log events to the Event Hub.
API Management loggers are configured using the API Management REST API
To create a logger, make an HTTP PUT request using the following URL template.

https://{your service}.management.azure-api.net/loggers/{new logger name}?api-version=2014-02-14-preview
Replace {your service} with the name of your API Management service instance.
Replace {new logger name} with the desired name for your new logger. You will reference this name when you configure the log-to-eventhub policy.


Add the following headers to the request.
Specify the request body using the following template.

{
  "type" : "AzureEventHub",
  "description" : "Sample logger description",
  "credentials" : {
    "name" : "Name of the Event Hub from the Azure Classic Portal",
    "connectionString" : "Endpoint=Event Hub Sender connection string"
    }
}
 Here is mine:












You will see that it returned 201 Created which means we now have a logger.


Now we go into APIM and add a policy on the built in echo API.



This will send event to our event hub when the



ProductUnlimited

APIEcho API
OperationRetrieve resource 

API is hit.


View the Event Hub Events

If you want to view the event hub events for your own sanity check then download Service Bus Explorer and listen to your event hub:





















You will notice that the event hub data shown in the listener is the same data written by our APIM policy.

Create Stream Analytics Job to send data to PowerBI

Next, go to your Azure portal and create a new stream analytics job.

Once it is created then create an input:







































And a PowerBI output: Note that you will be prompted to authorize your PowerBI account.








































Also create a query to transform the data. My query doesnt do anything special:



















Then start your stream analytics job.




















Now go back to your APIM instance and hit the API end point a few times. Make sure it is the API operation 
with the policy on it.

Also, change param1 and param2 on the operation to a few different values so we get somewhat useful data:


















Now look at the trace for that operation in APIM and you will see the log to event hub event has fired:
















Now log into PowerBI on the web and you will see (hopefully) a new streaming dataset:
















Create a dashboard


We will create a PowerBI dashboard to visualise our APIM data using param1 and param2


I will drag a pie chart onto the workspace and set the following: All I did was add param2 as a count. As you can see we get a great visualisation of the number of times param2 was used on the APIM operation.





























So you can see that I set a request with param2=5 a lot more times that I did for other calls.



Obviously you can use your imagination as to what you can use this for.

Here we see a Tree Map, Pie Chart and Funnel displaying data from my APIM. The funnel shows distinct calls from IP address.




thanks
Russ

Thursday, 28 April 2016

Error WAT200: No default service configuration "ServiceConfiguration.cscfg" could be found in the project.

Morning,

When deploying a cloud service / web role you may experience the following message:

2016-04-27T08:16:41.2709354Z ##[error]C:\Program Files (x86)\MSBuild\Microsoft\VisualStudio\v14.0\Windows Azure Tools\2.9\Microsoft.WindowsAzure.targets(373,5): Error WAT200: No default service configuration "ServiceConfiguration.cscfg" could be found in the project.

On your VSTS build screen:













It means it is basically looking for a default cscfg file as we havent specified an alternative.

In my build I went and set the Target Profile to match the build configuration and this fixed the issue.
















So it will be looking for one of the files shown below that match the currently building BuildConfiguration













And after those changes all builds perfectly:

















Thanks
Russ

Wednesday, 27 April 2016

Moving nuget package folder to a different location (1 level higher)

Hi,

Note: thanks to this post by sebastian belczyk for some help:
http://belczyk.com/2013/02/moving-nuget-packages-directory-outside-solutionss-directory/

This morning I need to relocate my nuget packages folder 1 level higher to allow an offshore team to work parallel with us. Basically, the original solution was cloaked and branched. In the original solution we realised we had 2 places for nuget packages so hence we had to merge them into 1 solution. This mean't that the branched solution need to match the original other wise we would have lots of reintegration issues.

Firstly, I needed to update my nuget.config file. We had our package located here:
../packages/
But we really needed them here:
../../packages/ - up another level.












Then I needed to close the solution and reopen it for this change to take affect. I found this out as changing the file without restarting meant that nothing changed and my packages were still restoring to the old ../packages/ directory.

Then right click to Manage nuget Packages for Solution ...


































Then Visual Studio will detect that there is no nuget packages folder on the file system at the location specified:














It will load them when you click restore:









So in summary, I had this file structure:
Soln
-- Project
---- packages Folder

And now I have this structure:
Soln
-- packages Folder
-- Project



thanks
Russ

Thursday, 7 April 2016

Move your IIS App pools from one machine to another

So,

Today I got a new machine and didn't want to have to set my IIS up again.

So I ran the following from a command prompt run as administrator:

%windir%\system32\inetsrv\appcmd list apppool /config /xml > c:\apppools.xml

This created an xml file with all my app pools in it. I deleted  6 nodes that held the default iis app pools:

  • DefaultAppPool
  • Classic .NET AppPool
  • .NET v2.0 Classic
  • .NET v2.0
  • .NET v4.5 Classic
  • .NET v4.5
Then I went to my new machine after copying over the edited apppools.xml file and ran this command:

%windir%\system32\inetsrv\appcmd add apppool /in < c:\apppools.xml














And all my app pools were added:























To export all my sites I ran this:
%windir%\system32\inetsrv\appcmd list site /config /xml > c:\sites.xml
It exported all my sites to an xml file. I edited this and removed the default web site as it was already present on the destination machine.

Then I ran this on the destination machine:

 %windir%\system32\inetsrv\appcmd add site /in < c:\sites.xml

And it imported all my sites into IIS:



































That is all,

Russ

Fix already installed nuget packages

Hello,

Sometimes I create a branch and for some reason 1 or 2 projects packages and hence Dlls are wrong. I even try using "Restore Nuget Packages" at solution level from the context menu but this doesn't always fix it.

The best fix I have found is this:
Update-Package PackageName -ProjectName MyProject -reinstall

So if you have Entity Framework 6.1.2 installed and it got broken in a branch then you could run:


Update-Package EntityFramework -ProjectName MyProject -reinstall

And it will reinstall EF 6.1.2

That is all,

thanks
Russ