VMware tools need to be installed and running on vApp. If VMware tools do not work correctly, some VMs can migrate to a not compatible host and then go back to the original host. In vCenter appears a message like: VMware tools are not running on virtual machine: [message]
The issue can occur during consolidation phase.
Possible solutions: control if VMware Tools are running on vCenter in the VM summary tab or directly on VM console through by the command service vmware-tools status. If the tools are stopped, reboot VM or launch the command service vmware-tools start on VM console.
The steps for re-Installation of VMware tools can be find in the following vmware article.
Posted in: VMware vSphere