There should only be one prefix you have to worry about and if you forget it you can look at any other computer on the network. Then just assign your servers each a small number.

For your case with VMs coming and going it would not be at all hard (and would probably result in better testing) to go the ISP route and assign a unique name to every address and then just report that name to your testers and devs. Reusing the name is exactly the same as reusing the ip address. Then you just have a series of machine names. testvm1, testvm2, testvm3, ... etc.

Really none of this is very hard, confusing or cumbersome. It just takes someone asking: "How do I make this work?" instead of thinking "Oh no! that is going to be horrible." and looking for excuses not to make it work.

The Republicans have a vision. The space shuttle pork still flowing despite the cancellation of the space shuttle. The republicans call the lack of pork lack of vision because the can't see anything to eat. The Republicans want a return to Apollo where the pork flowed more freely.

Now if someone really wants vision let me propose this. Charge NASA with laying the groundwork for colonizing the solar system. This should include the research (aka robotic probes) to figure out what is out there. This should include making space flight affordable and accessible without being a member of NASA.

Fundamentally space flight is affordable. Right now the fuel cost for a single person to orbit is about $70,000.

One way trips to Mars can be made as cheap as $500,000 if you believe Elon Musk.

A trip to Mars reduce to $500,000 is accessible to the middle class in the United States. Accessible to 100 million or more people. A colonization trip to Mars for $500,000 starts sounding like a good deal on a house given how silly housing prices are on the east and west coast of the United States.

So let's make the vision space flight and space colonization for the middle class. Let's laugh at everyone who suggests the vision for NASA is to give hand outs to the incumbent space companies and their over priced rockets.