Good morning my friends (not a good morning for us Canadians, specially Maple Leafs fans )
If you have Exchange Server running on your Hyper-V/SCVMM environment you may wondering how to make sure that you have same roles in different physical servers to avoid a hardware failure to bring outage to your users. Well, you can use the same post for DCs and all sort of servers.
In this post we are going to use a typical scenario where we have 2 CAS/HUB servers running on 2 VMs and the VMs run on a Hyper-V cluster and we want to avoid a physical harware failure to stop our CAS/HUB tier. In this environment we are running Windows Server 2012/SCVMM 2012 SP1 and the Exchange Server is 2010 SP3.
The key feature to use the Placement Rules is to take advantage of the Custom Properties which can be at Hyper-V Host, VM and so forth..
In the figure below, we are getting properties of a Hyper-V host (our first one) and we are going to click on Custom Properties and on the new page we are going to click on Manage Custom Properties..
In the new page, let’s click on Create and let’s label the new Custom Property as Default-Hyper-V-Host and then click on OK.
Back to the original page, let’s select Host on the object type field and let’s move our new property to the Assigned Properties side. After that, let’s select Virtual Machine and also add the new property there as well.
Now that we have the new property on either Host and Virtual Machine we need to assign values, for each host we are going to add their name to the property (SRV01 and SRV02 accordingly), and for the VMs we will specify which host that specific VM will be hosted by defining SRV01 or SRV02 at each VM level.
Creating the Placement Rules…
Awesome! We do have Hosts configured with their own names on the Default-Hyper-V-Host property and some VMs configured to the same values. Now, let’s click on the properties of a Host Group (the folder on the left side when working on VMs and Services) and then let’s click on Placement Rules…
Let’s create a new one and the rules are simple, we are using our new custom property and we can decide if it matches or not with the host and which action we should take (should or must) for that VM. We are playing safe here and let’s use the following rule: Virtual machine should match the host which means that if Host and VM have the same information on the Default-Hyper-V-Host property they should be together.
Live Migration testing…
We can test that in a really nice way, just move the machine the machine to another host and we will see that when the host that the VM is being moved is not the one that agrees with the Placement Rules we will have a warning on the rating explanation, as shown in the figure below.
Now, the next question that you may be asking yourself is the ability to do automatically.. I hope I’m right on this one. If that is your question, not a big deal, using SCVMM 2012 SP1 you can configure the Dynamic Optimization to take care of this, here is an example where I defined the level to High and every 30 minutes SCVMM will check and it will move machines around.