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Change the placement policy of your System Center Virtual Machine Manager configuration

Last week a colleague was creating a new test environment using the Team Foundation Server Lab Management features when we encountered following error:

Error when creating a new virtual machine on <machinename>:

TF259115: Team Foundation Server could not find any suitable host to deploy the virtual machine: <machinename>.

Contact your administrator to fix the issues on the hosts below. (Hosts are listed in brackets)

Memory requirement of the virtual machine(s) exceeds the available host resources. The placement policy for this host group is set to be conservative and hence virtual machines that are in stopped state are also accounted as consuming host resources. Your administrator can change this policy by running the TfsLabConfig tool.

As our lab management environment has a large set of virtual machines who are in a stopped state, we ran out fast of memory resources. We can change this behavior to exclude the non-running machines from memory usage. Therefore log on to your Team Foundation application server and run the following command from the command line:

TfsConfig.exe lab /settings /collectionName:defaultCollection /list

This command lists your current configuration settings for your lab environment.You will see that it is using a conservative placement policy. Run the following command to change the policy:

TfsConfig.exe lab /settings /collectionName:defaultCollection /hostGroup /edit /name:"All hosts" /labenvironmentplacementpolicy:aggressive

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