i am running a web-based online application and trying to achieve HA.
i created two windows vmss in an availability set.
All i am looking for is a simple failover protocol, what i am trying to achieve is when my Main Vm is down for any reason,my incoming traffic redirects to my Backup VM till the main vm is up and running again.
I know that Azure Traffic Manager can achieve this by using the Priority type and setting end points for Public Ips that assigned to my vmss.
But the traffic manager is using DNS in order to route traffics, there are some downtown before the traffic manager redirect traffic to my backup vm.
Please check this answer as well for more info why Traffic manager is not the solution. -even when i use fast-intervals settings-
https://stackoverflow.com/a/34469575/10786981
i also can't use load-balancer. As i need the Active/Passive model and load-balancer can't support this model.
A 3rd Load Balancer are expensive and we are really looking in to a simple solution here.
Related
Question: How do I host an endpoint in azure which allows me to redirect internet traffic at will between azure and aws services?
I am hosting two kubernetes clusters - one in Azure and the other in AWS. I want to be able to:
1. redirect the traffic at will to either aws or azure, whilst retaining the public dns endpoint.
2. fail over manually [and pref automatically too] to the aws cluster. What is the best way to host the endpoint in azure?
Requirements:
The traffic needs to be redirected immediately - no caching issues and stale loads!
Ability to configure failover - i.e. specify that Azure is hot and AWS is the failover service - the traffic should be automatically redirected as soon as Azure goes down.
I have looked at Traffic Manager, Load Balancers and Application Gateway. Not sure which one (if any) of these is best.
traffic manager wont work for you, since its a dns service, so caching will happen (admittedly its the best solution if you set dns cache to 5 seconds or something). application gateway allows you to specify an ip address as an endpoint, load balancers only work when attached to vms inside azure. But application gateways dont allow to failover at will. you would need to block the probe to failover.
Azure Front Door might be the solution for you (like the other answer mentions)
You can have a look into Azure Front Door Service for your usecase.
Look into this https://learn.microsoft.com/en-gb/azure/frontdoor/front-door-overview
Azure classic Cloud Services come with a built-in load balancer that allows a fast VIP swap from production to staging, and vice versa. What equivalent is provided by Azure Resource Manager? I can use DNS, but then I have the TTL delay.
I want the fast swap because my back-end servers are stateful and cannot process the same data in both staging and production without overwriting each other. In my current system, out-of-date connections (e.g. because of HTTP keep-alive) are rejected and a reload is forced, forcing fresh connections.
I guess I might be able to do it using Azure Application Gateway, but it is not listed as one of its features.
You can do VIP swap in ARM with 2 Azure load balancers by disassociating the public IPs, then reassigning them. It's not a fast deployment slot swap like you can do with cloud services however, as can take a minute to disassociate both IP addresses (you could speed this up by doing it in parallel), and based on your question you've already looked at this approach, but documenting it here as an option. There are some notes on this approach here: https://msftstack.wordpress.com/2017/02/24/vip-swap-blue-green-deployment-in-azure-resource-manager/
In Azure resource manager, there are three ways, Azure Load Balancer(layer 4), Application Gateway(layer 7) and Traffic Manager(DNS level). I think you can use Load Balancer in you scenario.
The following table helps understanding the difference between Load Balancer and Application Gateway:
We have a third party product run as a windows service, expose as a web service. The goal is to dynamically provision the service instances in business peak hours.
Just to run the thought with you guys,
- I've already deployed the service on multiple vm, configured the vm in the same cloud service Availability Sets, configured azure to turn on/off vm instances based on cpu use
- I am to configure a separate vm, run iss arr there, add points to the endpoints on the vm configured above, with the hope ARR balanced the requests to the back-end vm dynamically
Will this work? What's the best practice for the IaaS scale? Any thoughts? Truly appreciate the input.
If I have understood correctly, you just need to use the built in load balancer of the cloud service. Create a load balance set for your endpoint. For example, if you want to balace the incoming traffic to port 80 in your application all you have to do is to create a LB-set for this port and configure this set to all the VMs in the Cloud Service.
The Azure Load Balancer randomly distributes a specific type of
incoming traffic across multiple virtual machines or services in a
configuration known as a load-balanced set. For example, you can
spread the load of web request traffic across multiple web servers or
web roles.
Configure a load-balanced set
Azure load balancing for virtual machines
No matter if VMs are up or down, once it turns on and if the endpoint is configured in the same LB-set, it will automatically start responding to requests once port 80 is online (IIS started and is returning STATUS 200 OK, for example). So, answering your question: yes, it will work with auto-scale or manuallying turning on/off vms.
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)
I'm working on azure project and came across Azure Traffic Manager. Could someone please help me few question below:
Is Traffic Manager same as load balancer?
Do we need to create Traffic Manager manually or created automatically on webrole deploy.
How do I configure Traffic Manager with new Azure Mgt. Portal?
What is the main purpose of Poll State, as it says offline but I can still access using trafic manager url.
When we get proper CNAME, should CNAME point to this Traffic manager or url provided on Cloud Service > Dashboard?
Thanks.
Is Traffic Manager same as load balancer?
It can be used for failover or load balancing, although only in a round robin way.
Have a look here.
https://azure.microsoft.com/en-us/documentation/articles/traffic-manager-overview/
Do we need to create Traffic Manager manually or created automatically on webrole deploy.
You need to create it manually.
How do I configure Traffic Manager with new Azure Mgt. Portal?
Currently I believe you can only do it in the old portal.
What is the main purpose of Poll State, as it says offline but I can still access using trafic manager url.
Again easier to read this.
https://azure.microsoft.com/en-us/documentation/articles/traffic-manager-overview/
When we get proper CNAME, should CNAME point to this Traffic manager or url provided on Cloud Service > Dashboard?
If you want to use traffic manager to manage the traffic you point your CName to the traffic manager url.