I have azure cloud service with 2 instance count small vm so any one could explain how it internally use instances?
Both instance running parallel or run second instance when first one would go down.
Thanks in advance
They are both running in parallel. You should read about it on the Azure Docs: https://learn.microsoft.com/en-us/azure/cloud-services/cloud-services-choose-me
edit: Cloud Services includes the load balancer in front of your web role instances automatically for external endpoints.
Both are running in parallel and each cloud service has one URL with a load balancer and it forwards the traffic to both instances.
Related
Sorry guys if my question does not make sense. Let us say I have a website running in cloud. It is running under one instance.
I have a Scale out app service plan such that when CPU usage is more than 80% it creates one more instance. On day 3 let us say CPU usage gets to 85% and one more instance is created. My question is
1) Is it going to put a load balancer in front of these two instances.
2) Are these two Virtual machines going to be in different fault domain?
3) when I have two instances and I deploy from Visual studio, is it going to deploy to both instances?
1) Is it going to put a load balancer in front of these two
instances.
The answer is yes, after you enable autoscale settings, when your service receives additional traffic, you will get more instances without doing anything.
2) Are these two Virtual machines going to be in different fault
domain?
When multiple Cloud Service role instances are deployed, Azure deploys these instances to different fault domains.
More information about cloud service instances and fault domains, please refer to this blob.
3) when I have two instances and I deploy from Visual studio, is it
going to deploy to both instances?
No, after we deploy a new package, it will be applied in all instances of your WebApp.
More information about how to deploy APP to Azure app service, please refer to the link.
1-) Yes
2-) Probably, however I can't say this with 100% sure, because WebApps are PaaS, you delegate the management to Microsoft.
3-) When you deploy a new package it will be applied in all instances of your WebApp.
I'm using Azure for the first time to deploy a web app. More specifically, I'm using the Docker Container Service to do this. I already have one instance of it deployed. But, I want to also deploy 2 more instances of the same web app. I want each instance to have a different URL. What is the best way of doing this? Do I have to add a new container service for each new instance and repeat the steps I did for deploying the first instance?
As in case of Azure Container Service (ACS),
You choose a container orchestrator i.e. Swarm, DC\OS and Kubernetes (Because creating replicas works differently in each of them).
In case of Swarm then either create a separate application container for the same application with a different end point and use automatic discovery feature for different URL(s) or choose a reverse-proxy load-balancer such as Nginx which will work on the same URL but on a different port (My blog here might help you).
Creating replicas across a cluster are used for Load Balancing, Routing Mesh, Scaling and Rolling updates etc.
We deployed a Node.js Azure Web App and defined a minimum of 2 instances (for scalability and high-availability).
It seems like the LB is balancing the load between the instances, but it doesn't react on instance error (crash) and seems to insist balancing the load between all the instances including the one which crashed.
Is there a way to set a fail-over mechanism for high-availability?
The load balancer used by Azure App Service will continue to send requests to individual web servers as long as the underlying virtual machines are up and running.
To workaround the issue you are running into, you can try configuring the "auto-heal" feature. If the scenario is that the app gets "stuck" in a permanently broken state, auto-heal rules can be configured to automatically restart the app.
More details on auto-heal here:
Auto-heal for Azure Web Sites
In Azure, I have two Ubuntu VMs running the same python bottle services under one Cloud Service.
The two VMs are set to be in the same Load-Balanced Set and are load-balanced in a Round-Robin fashion under that cloud service.
However, my problem is that each request takes 3~8 seconds to get to the underlying VM. (i.e. The load balancer is working, but it's very slow routing the requests.) I assume it's not normal, is it?
It seems that I can't even access the cloud service instance(load balancer) in Azure. Can anyone give me a hint where I might have set wrong and resulted in this?
Thanks!
Is it any way of placing a WCF service in an Azure CDN Endopint? Or is it only valid to place static content?
It would be useful becasue I have a web frontend that constantly communicates with the WCF service.
If not, any suggestion on how to decrease delay?
If you want to run redundant WCF services in Azure, you create a WCF Service Web Role project and deploy it. Within the configuration, you can scale the deployment up to meet load. You can create and deploy multiple roles per package with each role having its separate instance count.
If you want the service to be distributed across multiple regions, you have to use the Azure Traffic Manager which handles directing traffic based on location or in a round robin format.