Summary

How are VM cloning or snapshots mitigated to prevent license leakage?

Question

Assume you have customers who operate within networks that are completely disconnected from the Internet. You're using an embedded license server which is preloaded with a certain number of licenses and installed on a machine on the network accessible to other machines. (The machine with the license server is not connected to the Internet).

Here's the scenario:

• The customer installs the embedded license server on a virtual machine (VM). They take a snapshot. The other machines will connect to this VM and obtain licenses. After all the licenses are consumed, the customer resets the VM to the original snapshot. Does that mean they will get to consume more licenses?
• Even if the embedded license server is not allowed in a VM, the customer can install it on a different machine and direct the software to use this different address to get more unpaid licenses. How is this handled?

Answer

Snapshot and clone are synonymous in terms of how this works in that the only differentiator is a generation (or time) gap. Trusted Storage (TS) is tied to the HOSTID, and if the VMUUID changes, then TS becomes invalid.

So it is dependent on what you tie the license to and if the UUID is liable to change after the image copy is re-instated.

A feature is tied to a particular client using a HOSTID value. In the default toolkit examples, clients are assumed to have a hard-coded string identifier '1234567890', while in practice your code specifies the desired type of client identifier (such as an Ethernet address) to examine at run time in order to compare it with the identifier in the license rights.

In addition, it is possible to tie the hostid to the VMUUID:

• UUID of a supported virtual machine: HOSTID=VM_UUID=uuid
• For example: HOSTID=VM_UUID=AAAAAAAA-BBBB-CCCC-DDDDEEEEEEEEEEEE

Essentially it behaves like FlexNet Publisher (FNP); if the UUID changes, there will be a license break. If it doesn't, then there will be no break. For a VM that has GenerationID, then this would not be an issue as the UUID will change if it is cloned (or copied/snapshot/whatever).

NOTE: With FlexNet Publisher, there are some caveats, such as the issue that the UUID will not change for VMWare. We are continually working on making this more robust.