I had a problem where I was unable to access some machines in the datacenter on subnet 172.16.16.0/24 from my OS X work machine.
Turns out vmnet8 was conflicting with the same subnet located at the Datacenter.
vmnet8 comes from my VMWare Fusion 8.x environment on the Mac, wherein I had some local virtual machines networking configuration for Internet Sharing “Share with my Mac”.
This was so they could leverage the vpn connection running on the OS X side of things and route over that to the Datacenter.
(You know the drill. Needing windows machines to admin bits of infrastructure because the vendors are behind the times and require windows only binaries for some of these things)
Here’s how I changed that conflict.
$ sudo vi /Library/Preferences/VMware\ Fusion/networking
$ sudo /Applications/VMware\ Fusion.app/Contents/Library/vmnet-cli --stop
$ sudo /Applications/VMware\ Fusion.app/Contents/Library/vmnet-cli --start