After trying everything I could find on the interwebs, the only way I could get two VMs on my Windows Server 2012 Hyper-V environment talking to each other was by enabling File & Printer Sharing and Network Discovery on the Guest/Public profile.
The problem is, this is on my live web VM (if you're wondering, I need my CI VM to be able to talk to it to do deployments). Basically, at this point, I just need to transfer files from the CI server to the web server. Currently I'm going through the default share (C$) but I can do something else if it makes more sense.
I have the CI VM talking to the DevWeb VM just fine without having to enable this, but they're both on 2012 R2, where the live web VM is just on 2012, so not sure if that is part of the problem.
Also, they're all connected through the physical NIC because I never could get some odd issues ironed out with the virtual NIC/switch.
Is there any other way around this, and if not, what risks am I incurring by doing this?
If needed, I can give you a list of some of the things I tried, but this is a pretty exhaustive list, and I probably won't remember everything, unfortunately (which I know is a bad sign).
Update
It's definitely related to the firewall, because as I tweak the settings under the "Allow an app or feature through Windows Firewall" settings, it affects my connectivity from CI to Web1 (live web VM). But the weird thing is, as I check a setting to get it working, I can go back in and uncheck it, and it still works.
I'm going to play some more with this tonight, and will post screenshots of the settings as I narrow down what's going on.
For what it's worth, this odd behavior is also evident on WebDev, where I've had no issues previously. And for now, the current settings are like this:
WebDev
Public Private
File and Printer Sharing No No
Network Discovery No No
Web1
Public Private
File and Printer Sharing No No
Network Discovery No No
But like I said, I've had them set exactly like this before, and changing nothing else but these settings will cause it to work -- and then I can change it back, and it still works. So not sure if something has to propagate, or if changing these settings is triggering something else outside the firewall settings.
Update 2
Ok, there's definitely a delay, because I just checked again (without changing anything), and it no longer works for either server. So whatever is causing this delay is making troubleshooting a major hassle.