Is Citrix Studio able to determine optimal placement from load when VMM used as hypervisor?

[zheise996]

I ask because it doesn't seem like it. We are currently in the process of transitioning away from VMware to Hyper-V/VMM. When I'd use MCS to Add Machines to a catalog on VMware, Studio was apparently looking at the load on each of the VMware host servers, because when the machine was added, it would be placed on a machine that would be able to run it.

Now, with 2 hosts moved from the VMware cluster to a new Hyper-V cluster managed by VMM, I have one host with RAM at 95% full, and the other at 5% full. I try to 'add machine' using Studio to the machine catalog - and Citrix Studio immediately places the new VM on the fully loaded host.

In VMM, when I uncheck the option on the loaded host's Properties -> Host Access "This host is available for placement" and then try to Add Machine, then Citrix Studio just fails after a few minutes with the error "ErrorID : Citrix.MachineCreation.DataModel.MachineCreationDiagnosticException TaskErrorInformation : Citrix.MachineCreation.DataModel.MachineCreationDiagnosticException: No hosts available."

So it seems Citrix is unable to ignore the host in the Cluster that is explicitly saying it doesn't want new VMs placed on it, and instead tries to place the new VM on it, then fails.

What sort of communication is Citrix Studio able to make with VMM to allow it to pick optimum location for placement?

[Michael Adam]

Hello @zheise996

 

if you move two hosts to MS VMM do you also configure both servers with the storage/network resources in the Citrix Studio Hosting Connection. If so the MCS deployment will create VM`s on all available storages.

While deployment MCS don`t care about RAM, but you can move the VM`s to a host with more available memory.

Regards,

Michael 

[zheise996]

Hi Michael, thanks for the response - that's interesting that MCS and Studio only look at storage space, rather than host usage.

Yes, I have my Windows Hyper-V hosts set up with a second drive, M:\ on both of them, that is meant for VM storage. Citrix Studio is configured to use the M:\ drive for both of the hosts, for both OS Storage and Temporary Storage.

Unfortunately, moving the VMs to hosts with more memory doesn't work with Hyper-V - as you know of course, when new machines are added, a little delta differential disk is spawned for the new machine, but it's just the changed blocks between the base image that lives on the host, and the new machine itself. So when I try to move a new VM from a fully utilized host to a less-utilized host using VMM, it breaks the entire VM system because it isn't able to copy the base image from the full host to the not-full host, and then the delta diff disk has nothing to link to. Here's a screenshot of the error that comes up in VMM when I tried to move a MCS-created VM from RDSHV11, to RDSHV08.

This means that in the Winstat-S817 citrix VM that was created, if I look at VMM's hardware properties for the VMM, the OS disk doesn't appear, since it was never copied over. Only the Citrix identity disk is there:

For comparison, here's what it should look like, using a working VM as an example. You can see how we have both an identity disk, and also a diff disk which uses a parent disk as its baseDisk.

So yes, I would love to be able to simply move Citrix MCS vms from one host to another based on resource utilization but it doesn't seem to work due to the disks not able to be copied.