All instances are not running in Azure App Service - azure

I am using Azure App Service which hosts application that reads data from Event hub using EventProcessorHost. I have allocated 6 instances(Manual Scaling) to run. I checked the Metrics(CPU Time) in App Service and found only 5 instances are running.
I am getting different instances count for different metrics.
Data In metrics shows 6 instances while CPU Time metrics shows 5 instances. I am confused. Please suggest.
Regards,
Amit Agrawal

the AlwaysOn feature is used to keep your app loaded, particularly when it's not receiving any traffic.
However, I am aware of numerous instances of AppServices, across a number of Azure Regions, where the metrics were showing the instance count different to the number of instances deployed. This was since yesterday. I believe there have been underlying Azure issues.
In the Azure Portal, under the menu for your WebApp, you should be able to see the recent health of your WebApp within the 'Resource Health' section.
I would advise that you raise a ticket with Microsoft, just to be sure.
#azurefamily

Related

Azure Functions metric to show number of concurrent hosts running

Is there a metric that I can look at to see the number of hosts running concurrently in Azure Functions? The functions are running in the Consumption plan.
If you have integrated Application Insights with Azure Functions, then you can see the number of (serverless) instances in the Live Metrics of Application Insights. Below is an example where you see two (serverless) instances - 1st and 3rd the ones that you see in the below image.
Integrate Azure Functions with App Insights, try to create some load and then go to Application Insights's Live Metric blade where you can view the servers running for your Azure Functions.
Update:
You can also view the instances in the "Diagnose & Solve Problems --> Availability & Performance --> Overview section..

Azure App Service shows 6 instances for Data In Metrics and showing 5 Instances for CPU Time metrics [duplicate]

I am using Azure App Service which hosts application that reads data from Event hub using EventProcessorHost. I have allocated 6 instances(Manual Scaling) to run. I checked the Metrics(CPU Time) in App Service and found only 5 instances are running.
I am getting different instances count for different metrics.
Data In metrics shows 6 instances while CPU Time metrics shows 5 instances. I am confused. Please suggest.
Regards,
Amit Agrawal
the AlwaysOn feature is used to keep your app loaded, particularly when it's not receiving any traffic.
However, I am aware of numerous instances of AppServices, across a number of Azure Regions, where the metrics were showing the instance count different to the number of instances deployed. This was since yesterday. I believe there have been underlying Azure issues.
In the Azure Portal, under the menu for your WebApp, you should be able to see the recent health of your WebApp within the 'Resource Health' section.
I would advise that you raise a ticket with Microsoft, just to be sure.
#azurefamily

Is a HostedService automatically scaled-out when AppService plan is autoscaling?

I have a .NET Core application running on Azure AppService.
I have also a hosted service interacting with a table and updating it according to a given condition.
I am experiencing an increase of CPU usage of just one of the instances when my autoscaling rules kick in and start scaling out the AppService.
My question is if HostedService is automatically scaled-out too when new instances are warmed up by autoscaling.
Yes they are. When you scale out, you have multiple instances of the same application running.
I figured this out the hard way. I was running a hosted service that sent out reports through emails once a day. After I scaled out to 2 instances, clients started receiving the same email twice a day.

How to get number of instances in time for Azure App Service

I have a website hosted on Azure and I was wondering how to get some info on the number of instances in time. I'm looking for info like this.
User XYZ changed the number of instances from 1 to 3 on 2018-09-18 10:00
This could be very useful also when autoscaling enabled. Is this kind of info available somewhere in the Azure portal? I was looking into Activity log and there seems to be some "Update hosting plan" operation but can't read the number of instances from it.
You can view the Run History to know the numbers of instances via Scale-out (App service plan) in your App service.
Alternatively, you can also get the specific instance info via Process Explorer for web app service. Ref: Monitoring your multiple Azure Web App instances
Update
I'm looking for kind of audit WHO and WHEN changed the number of
instances. Is it at least possible to retrieve the info from some
logs?
As for as I know, there is not exactly the same log as you expect. WHO is not specific somebody here since Autoscale setting enabled makes automatically increase or decrease the number of instances for your web app service. You can configure Autoscale settings to be triggered based on metrics that indicate load or performance, or triggered at a scheduled date and time. When an autoscale rule triggers, your scale set can automatically scale in. You can see the logs from click here to see more details in Run history.
If you have not enabled the autoscale, you do not activate the scale rules, the scale instances will not be triggered, so there is not a log for instances changes.
Ref: Understand Autoscale settings

Limit number of instances of a *standard* azure webjob when scaling out

Very similar to (but not a duplicate of!) this question: Limit number of instances of an azure webjob when scaling out
I would like to be able to limit the number of instances of a webjob within our standard webapp. I am aware of the possibility of having a singleton instance but would like to be able to limit this to a number other than 1.
Is such a thing possible? If not, are there any sensbile workarounds for the type of scenario described in q. 45067648 for those of us running on the Standard App Service?
Footnote on why this isn't a duplicate of q. 45067648:
I asked the previous question without considering that there could be a different answer depending on whether the app service was running on a premium or standard SKU. The answer Amor gave would be an ideal answer for those running on the premium SKU but is unsuitable for those running the standard SKU. I considered amending the original question but, after advice on meta (here and here), discovered this is best posed as a new question
limit the number of instances of a webjob within our standard webapp.
Under "Create a continuously running WebJob" section in the article, you can see: "If your web app runs on more than one instance, a continuously running WebJob will run on all of your instances". And it enables us to make continuous WebJob to run on only one instance.
To limit the number of instances that continuous WebJob run on, Amor has gave you a workaround in this thread: using Per app scaling feature (available only for Premium SKU App Service plans). If you do not want to scale your Standard SKU App Service plan to Premium SKU App Service plan, you can create another new Standard SKU App Service plan with specific number of instance that you want to run your WebJob, in this way, your WebJob will not cause resource contention with other web apps.
Besides, you can give a feedback on Azure UserVoice.

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