Note: I'm still in learning phase.
Question: For the scenario described below, in the Load Balancing Settings for the two VMs for the FrontEnd subnet should I choose Application Gateway or Azure Load Balancer?
In Azure portal, when I create the VMs for FrontEnd, the Networking tab of the wizard, gives me two choices shown below:
Why the confusion:
For Load Balancing Internet Traffic to VMs, this tutorial does not choose Application Gateway. But the 5th bullet of the following scenario seems to indicate I should choose Application Gateway
Scenario
This tutorial from official Azure team describes designing an infrastructure for a simple online store as follows:
The above configuration incorporates:
A cloud-only virtual network with two subnets (FrontEnd and BackEnd)
Azure Managed Disks with both Standard and Premium disks
Four availability sets, one for each tier of the online store
The virtual machines for the four tiers
An external load balanced set for HTTPS-based web traffic from the Internet to the web servers
An internal load balanced set for unencrypted web traffic from the web servers to the application servers
A single resource group
you can use both, its a matter of your needs. load balancer just forwards traffic to your vms, while application gateway can do path based routing, ssl offloading, has WAF capabilities, and so on. But it costs a lot more and is clunky.
Looking at the bullet points you've listed, your case will work with both of these solutions.
ps. Like Rahul mentioned, load balancer works on level 4 and is not HTTP aware, Application Gateway is a level 7 load balancer.
Related
Just wanted the recommendations in using azure frontdoor or azure traffic manager for my 2 different web apps hosted on different regions? Can we use both together?
Both Azure front door and traffic manager are deployed in a region agnostic way by azure to help load balance instances between region pairs. If you are hosting web applications using azure app service, the recommend solution for load balancing between regions is Front Door since your traffic is Http(s). (whereas a traffic manager would work nice if you are running virtual machines in different regions and want to load balance between them)
And if you want to further load balance traffic between different web apps in the same region, use an azure application gateway. (your front door directs user traffic to a region, and within that region, the application gateway directs traffic to a healthy web app.)
You can read this for a decision tree of the load balancing options provided by microsoft : https://learn.microsoft.com/en-us/azure/architecture/guide/technology-choices/load-balancing-overview#decision-tree-for-load-balancing-in-azure
IMHO you should use the one that makes more sense. Traffic Manager you can work with different algorithms when routing to the right region, while Front Door you don't have this flexibility.
On the other hand, Front Door offers some features like Web Application Firewall (WAF) and SSL Offloading that may be interesting in your scenario.
In Azure, I have 3 Web Apps (for simplicity):
Frontend website
Endpoint 1
Endpoint 2
The frontend website requests data from an endpoint.
Both endpoints are synchronized all the time (outside the scope of this question), but sometimes I need to do some maintenance on them, which gives me some downtime.
Can I somehow setup a loadbalancer only my frontend website can see, and get any of the online endpoints - like this:
The last line of this article says Internal Load Balancers might be the fit:
Can I use ILB on PaaS services (Web/Worker roles)?
ILB is designed to work with web/worker roles as well, and it is available from SDK 2.4 onwards.
Does anyone know of a guide, or have tried making this with Web Apps?
I dont think this is something you can achieve "natively" with load balancers. App Services are not actually bound to the VNet. Previously you could only use point-to-site vpn to connect them to vnet, right now there is a new vnet integration feature in preview which might allow you to use internal load balancers, but I doubt that, because they (load balancers) only allow to use virtual machines\scale sets\availability sets as backend pools.
Application gateways can be bound to the App Services. And they can be internal as well. You'd also need to restrict App Service(s) to receive traffic from anything that is not you Application gateway.
You can use traffic manager\front door for this sort of load balancing, but the endpoints won't be private
If two logic apps are there in two different regions and I want to do load balancing between these two how to do this.
Through some source, I got to know that it is possible through API management but they have not mentioned how to do this.
So, how to do load balancing between two logic apps?
Well...why do you want to do this? "Load Balancing" especially with LogicApps is fundamentally different on Azure than on-premise or self hosted. It's not wrong, just different ;)
What they were probably referring to was Azure Load Balancer which appears as a Networking Service, not APIM.
This, you can use to distribute requests as you would with traditional load balancers.
Since you want to load balance across regions I would look into Azure Traffic Manager. Traffic Manager is a DNS load balancer that sits outside/above Azure regions and allows you to have traffic balanced based on various performance profiles (i.e. Weighted, Performance, etc.)
High Level / General steps are:
Setup Logic Apps in 2 Regions
Create and register public dns domain for the logic apps - apps.foo.com (done outside Azure typically)
Point your DNS record for apps.foo.com to Azure Traffic Manager
Add endpoints to Azure Traffic Manager for Logic App in Region 1 and Logic App in Region 2 and setup your traffic manager profile
Calls to the Logic App start with the custom DNS domain get routed to ATM which then distributes to the regions based on your configured profile.
At the moment, we are using Azure Traffic Management to provide Load Balancing and High Availability across multiple regions for Azure App Services deployed on App Service Environments. We have reduced the Traffic Manager TTL to 30 secs. However, some of the clients have DNS cache (4 hours TTL) which we cannot control and this impacts the availability of our solution.
What would be a good alternative to provide HA and LB to Azure App Services which does not rely on DNS? We have seen on the documentation that MS suggests third-party solutions, but are there any particular suggestions?
Thanks,
As you point out, Azure Traffic Manager operates in the DNS layer. If you are looking at managing multiple endpoints for high availability and load balancing outside of DNS layer, I would recommend considering Azure Application Gateway (for HTTP workloads) and / or Azure Load Balancer (for any layer 4 (TCP, UDP) load balancing).
You may also find this article on Combining Load Balancers in Azure relevant for your use case
I am evaluating the convenience of moving to azure. Currently, I am trying to figure out how to balance the load and make routing for different websites on the same machine. I saw tutorials where a user created a separate LB on a different VM. I also found many articles about the possibility to balance the load using Azure load balancing.
So I assume both are possible, is that correct?
I would like to know how to connect between machines on azure. Would it be possible to do so using a local ip, machinename, or dns?
I also need to figure out how to forward traffic to different ports based on http header, is that possible without a seperate machine as load balancer? I see the endpoint config in my azure dashboard and found the official documentation, but unfortunately it's not enough for my understanding.
Currently, I am trying to figure out how to balance the load and make
routing for different websites on the same machine.
You can have different web sites on the same machine by configuring virtual hosting on IIS. This is accomplished using host header. VM, Cloud Service or even Websites supports this functionality. VMs and Cloud Services should be pretty straight forward. Example using websites:
Hosting multiple domains under one Azure Website
http://blogs.msdn.com/b/cschotte/archive/2013/05/30/hosting-multiple-domains-under-one-azure.aspx
I also found many articles about the possibility to balance the load
using Azure load balancing.
LB for VMs are as easy as creating a load balance set inside endpoint configuration wizard. Once you create a balance set, for example, enpoint HTTP port 80, you can assign this balance set to any VM on the same cloud service. All requests to port 80 would be automatically balanced across all VMs in the set.
So I assume both are possible, is that correct?
Yes.
I would like to know how to connect between machines on azure. Would
it be possible to do so using a local ip, machinename, or dns?
You just have to create a virtual network and deploy the VMs to it. Websites (through preview portal only), Cloud Services and VMs supports VNet.
Virtual Network Overview
https://msdn.microsoft.com/library/azure/jj156007.aspx/
I also need to figure out how to forward traffic to different ports
based on http header, is that possible without a seperate machine as
load balancer?
Not at this moment. Best you can have with native Azure Services is a 3-tuple (Source IP, Destination IP, Protocol) load balance configuration.
Azure Load Balancer new distribution mode
http://azure.microsoft.com/blog/2014/10/30/azure-load-balancer-new-distribution-mode/
depending on how you're deploying there's a couple of options:
first of all: LB sets in VM's in a cloud service. For this the Cloud service acts as the LB. this can only be achieved when using a standard sku VM.
second of all in Azure WebApps : load balancing is achieved automagically when deploying through standard means, since scaling is foreseen here.
Third of all there's Cloud Services with roles, who also do this "automagically".
Now none of that seem to apply to your needs. you can also start thinking about using traffic manager, something with a little more bite :-)
have you read this article by any chance? http://azure.microsoft.com/en-us/documentation/articles/virtual-machines-load-balance/
I'd like to advise you to add different endpoints to your VM's work with traffic manager and ake sure you IIS has all the headers on the correct ports (cause i'm assuming that's what you're doing already)