What would be the impact of cloning a VM with the Tentacle agent already installed and connected to an Octopus Server?
Should Just Work. After you spun up the second clone and renamed the machine, you’d just have to add it to Octopus.
As far as the Octopus is concerned, the Tentacle is just a URI (http://foo:10933/) that exposes a wsHttpBinding WCF service. No other assumptions about machine names/SSIDs/etc. are made.
For anyone visiting this thread post-Octopus 2.0, this is no longer safe to do. See the section “Cloning Tentacle VMS” in http://docs.octopusdeploy.com/display/OD/Installing+Tentacles for more information.