Struggled through this tonight.
Launched my OS X Juniper Network Connect VPN client, grabbed source code for a new project and started setting configuring my system to run it. Edited the
/etc/hosts file to add the virtual host name to it. Project was working at that point. A little later I disconnected from VPN and when to work on the project again and nothing worked.
Apparently the Network Connect VPN client made a copy of the
/etc/hosts file and added a few lines at the top of the file. I noticed it, but didn't think anything of it. When I disconnected it reverted to the original version. That blew away the changes that I made, and the reason nothing worked.
Very frustrating trying to debug that when I knew I had made the proper changes. Moral of the story, don't edit a Network Connect VPN created
/etc/hosts file, it will revert to the original version when it disconnects.