I have created an Azure load balancer with Azure resource manager template, but could not figure out how to associate new listeners, rules and probes defined in an extra template to the existing load balancer.
The motive to do this is utilizing one load balancer to route traffic to several applications running on the same virtual machine scale set through different port.
Related
I am using VMSS with basic tier load balancer and public IP address. When I am doing application update, I want to create new VMSS to make sure it is not affecting the old VMSS. Now I am creating new VMSS with new IP and load balancer. However, I do not want the IP to change. Is there any way to create a new VMSS connecting to an existing basic tier load balancer?
You cannot add multiple Azure VMSS to one Basic tier Azure load balancer.
Azure Basic load balancer only supports virtual machines in a single availability set or virtual machine scale set (this is a single VMSS).
Reference : https://learn.microsoft.com/en-us/azure/load-balancer/skus
However, Standard load balancer supports any virtual machines or virtual machine scale sets (multiple) in a single virtual network.
So, you can easily configure a VMSS with an existing Standard SKU load balancer using the Azure portal:
https://learn.microsoft.com/en-us/azure/load-balancer/configure-vm-scale-set-portal
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.
I am maintaining a azure cloud service which has 1 web role and few worker roles. The webrole has multiple instances. When I open the cloud service from the resources, I can see the service endpoint and public ip address. I want to understand how is the traffic load balanced in this azure cloud service. I searched for load balancers but I could not find it in the subscription. I was also not able to get the reference of some document which explains load balancing in the cloud service specifically.
Any info in this regard?
Long story short,
The default distribution mode for Azure Load Balancer is a 5-tuple hash. The tuple is composed of the source IP, source port, destination IP, destination port, and protocol type. The hash is used to map traffic to the available servers and the algorithm provides stickiness only within a transport session.
https://learn.microsoft.com/en-us/azure/load-balancer/load-balancer-distribution-mode
Internal load balancer is supported for cloud services. An internal load balancer endpoint created in a cloud service that is outside a regional virtual network will be accessible only within the cloud service.
I found these docs which might be helpful to you. These explain setting internal load balancer for cloud services.
Classic : https://learn.microsoft.com/en-us/azure/load-balancer/load-balancer-get-started-ilb-classic-cloud
ARM : https://learn.microsoft.com/en-us/azure/load-balancer/load-balancer-get-started-ilb-arm-ps
Just to make it clear, the information below is about classic services. For information about classic and resource manager model, see this page.
In cloud services you get a load balancer automatically configured when you create the service. If you want to configure it, you can do so using the service model.
The load balancer can be of two different types,
internal load balancer
external loab balancer
The internal one can only be accessed inside the cloud service, while the external one got a public IP. See this page for how to make an internal load balancer.
Load balancers keep track of the health state of the endpoints by regularly probing them. Check out this page for how to configure the probing. As long as the internal services return a HTTP 200, they are kept in the load balancers pool.
Have a look at this page for more general information on load balancers for cloud services.
Also, see this page as well. It contains a good information about the service.
I created a Scale Set (using a template) with an existing virtual network.
This existing virtual network has already a Load Balancer (with a public IP) with specific VMs.
Now, I can't connect to the VMs in the scale set, There's no option to add the scale set to the Load Balancer or to add the scale set's VMs to the Load Balancer. Creating a new Load Balancer doesn't help.
It seems that the only option for adding a backend pool is using an availability set or a single VM (which is not in the Scale Set).
Is there any way to solve this? to somehow add the Scale Set to the Load Balancer or to connect to it?
The goal was to create the scale set to be in the existing Load Balancer (in the network with the other VMs), but unfortunately it didn't work.
It is not posible to add vms in different availability sets to the same lb. VMSS has its own availability set (by desing). so this is not possible.
https://social.msdn.microsoft.com/Forums/sqlserver/en-US/ccf69a9c-0a6a-47bc-afca-561cf66cdebd/multiple-availability-sets-on-single-load-balancer?forum=WAVirtualMachinesVirtualNetwork
You can work around by creating vm in the network that will act as a load balancer, but that's obviously not a PAAS solution
The goal was to create the scale set to be in the existing Load
Balancer (in the network with the other VMs), but unfortunately it
didn't work.
It is not possible and no need. Please refer to this official document. Azure VMSS instances are behind a load balancer. Also VMSS's intance could not add to a existing load balancer.
Now, I can't connect to the VMs in the scale set.
Do you create inbound NAT rules for your instance? Also, you could create a jump VM in the same VNet to login one instance. See this question.
If you could not login your VM from a jump VM, it is not a VMSS issue. You should check your instance. If you don't do any change for your instances. You could create a ticket to Azure to solve this issue.
I want to create a load balancer for all my agents.
In the official docs I found a guide for an external load balancer, but I want to connect it with the api management so it has to be only visible in the vnet.
This post works if you only have one agent (you enter the private ip of the agent in your api route). But it does not handle the second agent.
Is it possible to use Azure API Management and Azure ACS (kubernetes) as frontend and backend?
So in my case I need to create a load balancer that handles all agents for the service and has a private ip in a vnet in that the api management service also is.
well, nothing prevents you from connecting api management to an external endpoint, so there's that.
and if you really want internal endpoint I doubt that it is possible, since a NIC can only be attached to a single load balancer. maybe if you detach agent nics from the external load balancer and attach them to internal load balancer... that might work, but looks like a solid hack.
other way around this might be using ACS engine to generate a template for you and alter the template to deploy internal load balancer.
As 4c74356b41 said, we can't add a VM to two backend pools (if your k8s create via azure portal, the agents in a VMSS.)
In your scenario, I think we can create a VM in ACS resource group, and install load balance software on it, make this VM work as a load balancer.
For example, we can use Haproxy to load balance the network traffic to agents.