When creating a VM in Azure, you have the option of setting an Availability Set and Fault/Update domain. I have some VMs where I need to set the Availability Set and another set of VMs where I need to update the Fault/Update domain.
As far as I can see, this isn't available with the new Resource Group-based Virtual Machines and cmdlets, thus this previous post isn't applicable. Without recreating the VMs, what is the proper way to set these resources?
Because availability set membership determines which stamp (cluster) a VM will be created in, it isn't possible to configure the availability set after the machine is deployed.
The simplest solution would be to delete the VM, while retaining the disks, then create your availability set and create and add new VMs with the existing disks.
Related
I have a AvailabilityZone set to my deployed VMSS, i would like to know how can i add and change AvailabilityZone to my current vmss but i cant find any option to do so.
I would really appreciate any inputs
Change the Availability Zone Sets
You can't add an existing VM to an availability set after it's created. VMs must be created within the availability set to make sure they're correctly distributed across the hardware. A VM can only be added to an availability set when it is created. To change the availability set, you need to delete and then recreate the virtual machine.
Please refer to the below documents for more information :- https://learn.microsoft.com/en-us/azure/virtual-machines/windows/tutorial-availability-sets
https://learn.microsoft.com/en-us/azure/virtual-machines/windows/change-availability-set
We want to convert to managed disks in our azure virtual machines. We first need to convert the availability set to managed. During the conversion of the availability set is downtime expected?
Azure availability set has two SKUs.
use managed disks(aligned)
not use managed disks(classic).
If you migrate availability set to a managed availability set, there is no downtime for availability set migration. After you click convert button, you will begin to migrate the availability set.
After your availability set has been changed to managed type in the overview in the availability set portal. The VMs in this availability set is still using unmanaged disks, you can change unmanaged disks to managed disks for these VMs.
However, the conversion from unmanaged disks to managed disks requires a restart of the VM. You could refer to this official doc: Convert a Windows virtual machine from unmanaged disks to managed disks
I am not very familiar with this in azure.
I created one centos vm, I created an availability set, in order to enable auto scaling I need to create another VM in the same availability set.
so I will create another vm, with the same image.
So, these 2 vms will replicate each other? if I install something in one VM, will it be replicated automatically to the other vm?, should I use only one of the vms as the starter point to install and configure things?
or should I do everything manually on each VM? Example, if I open port 80 in one I should do it in another?, if I install magento in one, I should install it in the other?
Azure will not replicate your VMs automatically. There are some manual steps involved:
You need to prepare one VM as a starter point.
Then you manually clone VMs up to a maximum number that you will need.
Make sure all they are in the same availability set.
Set up auto scaling
Now Azure will scale automatically by turning some of your VMs on and off. When VM is turned off, you will only incur storage costs for it. And storage in Azure is almost free.
To answer your first question: How to configure availability set
I created a post covering this on How to guard your application from azure outages
Use the quick create to stand up a VM of your choice
Once the instance is running click on the configure tab and create a new availability set
Click save
Saving will force a shut down, reconfigure, startup process
Once the VM comes back online you can create a 2nd VM
Using the create from gallery option, click through all the create screens until you get to the configure virtual machine screen (screen 4 at the moment)
Select the cloud service that was created with your first VM (availability sets require the VM's to run in the same cloud service)
Then select the availability set you created for the first VM
Finish the creation of your second VM
You can now see the linked VM's in the same availability set by clicking on the configure tab for any VM in the availability set you created. It will list all VMs in a given availability set inside the details of the VM
I just created a standard vm inside Azure, and created a new Availability set.
I created another vm, with the same specs, in the same region, but when I go to configurare the availability set I don't see it in the list.
I'm missing something?
Luca
So... just posting this as an answer, to properly close the loop based on the comments under the question:
When setting up a Virtual Machine, you can choose which Cloud Service to place the Virtual Machine in. The Cloud Service is essentially a container which gets assigned a specific IP address, gets a cloudapp.net name (e.g. myservice.cloudapp.net), and gets assigned to a region (or affinity group, which is region-specific).
Availability Sets are specific to a given Cloud Service. You may place any of your Cloud Service's VMs in the same Availability Set (or even have multiple Availability Sets, with groups of VMs assigned to specific Availability Sets). However: An Availability Set does not span across Cloud Services.
So: When you went to set up your second Virtual Machine, and you didn't see your Availability Set, that is because you were attempting to deploy to a different Cloud Service.
Below screenshot shows the wizard page where we can select existing cloud service to which we can associate a new VM
I want to create two virtual machines in Azure which should not be connected to each other. I created first virtual machine and also created an availability set as part of its creation process.
Now when I create the second virtual machine then I don't get the availability set created as part of first virtual machine in the drop down list of availability sets.
However if I try to connect the second virtual machine as part of first one then I am able to see the availability set created as part of first virtual machine.
Is it mandatory for virtual machines to be connected to each other so that I can add them to the same availability set? Is this a limitation only from azure portal and there is a workaround using powershell?
UPDATE:
If we connect two virtual machines then we can get the benefit of availability set. However, at the same time both virtual machine becomes part of same cloud service and hence are load balanced by azure which does not support sticky session.
My scenerio is that I have identical front-ends which needs to support sticky session. Therefore I don't want to connect them to each other. However, I want to get the benefits of availability sets as mentioned in the article on Availability sets.
So can I set availability set for two identical virtual machines not connected to each other?
The term "Availability Set" means that you want to bring one or more VM within one service group for maximize the availability during an event of downtime. So what you see on Azure Portal is correct behavior however you might have some misunderstanding with regard to Availability Set. You can read more on "Availability Set" here.
So when you try to connect second virtual machine as part of first, you do see the availability set, because this way you want your VM to use the settings from the first and add another VM to the same group to maximize the availability. This second VM becomes the part of first one.
When you create an independent VM (call is second or 3rd or any) you are actually creating a brand new VM which is going to run independent to any other VM you may or may not have and thats why you dont see "availability set" instead you can create a new "availability set" based on this new VM.
Set AvailabilitySet using Powershell
Get-AzureVM -ServiceName "savilltech101" -Name "WebSrv3" | Set-AzureAvailabilitySet -AvailabilitySetName "IIS" | Update-AzureVM