Is it possible (and how) to load balance Azure web sites?
Situation is that I have a web site which I deployed to few redundant nodes. Now I would like to set up load balancing for reliability purposes.
I see that load balancing is done using Traffic Manager service which I tried to use, however Traffic Manager doesn't allow me to add a web site endpoint. It only allows me to add a custom virtual machine I have. On a side note, web sites are running in standard mode which means each runs on it's own VM which led me to believe I could load balance them.
I see people create separate VMs with Windows Server and use IIS ARR to perform actual web request load balancing. Is there a way in Azure to load balance web sites directly?
While converting over to web roles can very well suit your needs, an easier alternative may be to simply promote the web site up to the 'standard' tier, then increase the instance count. Windows Azure will then automatically handle load balancing the instances and even help ensure session affinity (which web roles can't do unless you jump through additional hoops).
Why not make your sites use Web Roles?
This only requires a very small change to the project to add a startup class.
These are automatically load balanced.
You are required to have at least two role instances to trigger the SLA.
Related
I am creating a network with 2 app services, containing 2 slots each
I know the load balancers are designed to work with VM's, but I am wondering if it is possible to place a load balencer on these 2 app services to balance the load between them, Is it possible to do so??
When you Scale your Web App you add instances of your current pricing tier and Azure deploys your Web App package to each of them.
There's a Load Balancer over all your instances, so, traffic is automatically load balanced between them. You shouldn't need a Virtual Machine for this and you don't need to configure any extra Traffic Manager.
You may want to refer: scale your app in Azure App Service for more details.
but I am wondering if it is possible to place a load balencer on
these 2 app services to balance the load between them, Is it possible
to do so??
According to your description, maybe you are looking for Azure application gateway(layer 7).
Azure application gateway works at the application layer (Layer 7 in the OSI network reference stack). It acts as a reverse-proxy service, terminating the client connection and forwarding requests to back-end endpoints.
Azure application gateway support HTTP, HTTPS and Websockets.
Here is the features offered by each service:
More information about Application gateway, please refer to this article.
Maybe little late but I guess this what you are looking at
Scale Out- A scale out operation is the equivalent of creating multiple copies of your web site and adding a load balancer to distribute the demand between them. When you scale out a web site in Windows Azure Web Sites there is no need to configure load balancing separately since this is already provided by the platform.
https://azure.microsoft.com/en-us/blog/scaling-up-and-scaling-out-in-windows-azure-web-sites/
We have a new requirement, summary follows,
Around 30 sites to be developed.
Should use Umbraco.
All the sites should need have a common Umbraco backend.
Single SQL DB.
Some of the sites will be bilingual.
Load balancing architecture required.
We did the POC for the same with 3 sites in a single instance of umbraco by adding root nodes and assigning proper host name, permissions etc and it worked fine.
But in the real case, will it work smoothly ?
We checked the following article regarding flexible load balancing in Umbraco and planned to move with Azure as it is mentioned as the first choice in the article here.
Is anyone has any similar kind of experience ?
Please share, your help would be greatly appreciated.
AFAIK, Azure Web Apps support Built-in autoscale and load balancing. I assumed that web apps leverage Application Request Routing. ARR Affinity is enabled on your Azure App Service by default. This means that if you are running multiple instance of your App Service, clients will be directed to the same instance for each request. For more details, you could refer to here.
Also, you could leverage Traffic Manager with your azure web app for load balancing, which could distribute the traffic to your web app endpoints in different datacenters (global route traffic).
Here are some tutorials, you could refer to them:
Create a Traffic Manager profile
Scale up your app by changing the pricing tier, then you could get more CPU, memory, disk space, etc. For more details, you could refer to Scale up your pricing tier.
Scale out your app to multiple instances manually or automatically based on your configured performance peaks. For more details, you could refer to Scale instance count manually or automatically.
I have my website (abc.azurewebsites.net) hosted to Azure Web Apps using Visual Studio.
Now after 1 month I am facing problems with traffic management. My CPU is always 90 - 95% as the number of requests is too high.
Does anyone know how to add Traffic Management in this web app without changing the domain abc.azurewebsites.net? Is it hard coded in my application?
I thought of changing the web app to a Virtual Machine but now as it's already deployed I am scared of domain loss.
When you Scale your Web App you add instances of your current pricing tier and Azure deploys your Web App package to each of them.
There's a Load Balancer over all your instances, so, traffic is automatically load balanced between them. You shouldn't need a Virtual Machine for this and you don't need to configure any extra Traffic Manager.
I can vouch that my company is using Azure Web Apps to manage more than 1000 concurrent users making thousands of requests with just 2-3 instances. It all depends on what your application does and what other resources does it access too, if you implemented or not a caching strategy and what kind of data storage you are using.
High CPU does not always mean high traffic, it's a mix of CPU and Http Queue Length that gives you an idea of how well your instances are handling traffic.
Your solution might implementing a group of things:
Performance tweak your application
Add caching strategies (distributed cache like Azure Redis is a good option)
Increase Web App instances by configuring Auto-Scaling based on HTTP Queue Length / CPU.
You should not have to change your domain to autoscale a Web App, but you may have to change your pricing tier. Scaling to multiple instance is available at Basic pricing tier, and autoscaling starts at Standard tier. Custom domains are allowed at these levels but you don't have to change your domain if you don't want to.
Here is the overview of scaling a web app https://azure.microsoft.com/en-us/documentation/articles/web-sites-scale/
Adding a Virtual Machine (VM) is very costly as compared to adding instance. On top of it, Redundancy (recommended) for the VMs, adding NIC etc will blow up the cost. Maintenance is another challenge. PAAS (webApp etc) is always a better option than IAAS.
Serverless offerings like Azure Functions can also be thought of. They support http trigger and scale up really well.
I am trying to scale a web app on Azure from a single web instance to multiple instances. The web app does a fair amount of processing of per-user state, it's also fairly interactive so latency is important. We currently have a single database, testing has shown it is not the bottleneck so for this question let's assume we don't have to worry about scaling it, all instances will hit the same database. In this case, I think per-user load balancing is the best option, as per-request will result in per-user state being duplicated in lots of web instances. Apart from the issue of maintaining consistency, I am concerned this would result in unacceptable latency for end users.
This link says that ARR does per-user load balancing by default on Azure. However, the Traffic Manager, which from what I can gather is automatically enabled when you spin up multiple web instances on Azure, does per-request load balancing.
So my question is, which of these two load balancing schemes will I be using if I add a few more instances to my Web Hosting Plan? If I need to manually disable the Traffic Manager, what is the best way to do this?
Calum - you can leverage the standard SQL Session State Provider in Azure or you could look at the Azure Redis Cache provider as well for backing stores for user session state.
When deploying to Cloud Service Web Roles you automatically get a load balancer instance in front of your hosts. It's relatively transparent other than configuration of Endpoints. Each newly added/removed auto-scaled instance gets added to the Cloud Service and is automatically added/removed to the load balancer.
As others have said, Azure Traffic Manager provides a higher level service which can direct traffic to multiple Azure Regions (data centers) and even on-premises endpoints.
A good overview of Load Balancing can be found here: http://azure.microsoft.com/blog/2014/04/08/microsoft-azure-load-balancing-services/
We have a client that we have setup two webservers running about a dozen different websites spread over each webserver for each site (so site 1 is running on both webservers, site 2 is running on both ect).
We want to setup load balancing (presumably with Traffic Manager) so that it will spread the load and monitor the sites availability across both the web servers per site and not per virtual machine like the regular Azure load balanced sets do.
It seems that traffic manager might be able to do this but we don't know how it works and the documentation is not clear to us about if we can setup the TM per website and not per web server (as we understand it).
Can we setup any load balancing in Azure that will monitor the website itself and not the virtual machine? Because we want to run multiple sites on these two web servers, how do we setup TM do allow this to happen? Do we make a new TM service for each website?
thanks in advance.
UPDATE: do we even need to setup the regular load balancing set at all? Can I not just create a TM and click on the cloud services of each of the web servers and then add the port and relative path to one of the websites? and just repeat this for each website on the two servers? would that be how it should be setup?
Thanks again.
The available endpoints you can define in your Traffic Manager definition is only as granular as your cloud service URLs. So, the quick answer to your question is no.
You may want to look into using Application Request Routing in front of your two servers instead. It does introduce additional server(s) in your configuration but will give you a way to load balance across the sites.
http://www.iis.net/downloads/microsoft/application-request-routing
The answer to this question was custom end points from traffic manager. This will allow Azure to be able to monitor the service for each service or website on a web server within Azure.