The Sentinel web page (http://localhost:1947/_int_/products.html) indicates Licenses:
"Disabled due to Cloning"
The Safenet Sentinel Licensing mechanism will invalidate the licenses due to cloning if it detects any changes with the Hardware IDs of the VM Image. In order to prevent this we suggest the following:
1) Make sure the Image UUID is static
2) Make sure the MAC Address of the Network Adapter is set to Manual (static MAC Address)
The other workaround is to use a real hardware host to act as a License Server. Every VM host can check out a license from the License Server before a test is run.