You can host HipChat Private server as long as you can bring it up using the formats provided (ova and ami). Not though that you'll still be using a couple of cloud services (the push notifications and video). Your best bet might be to ping email@example.com with the specific concerns.
In addition to Daniel's answer, you should have issues to install HipChat server over VPN.
If you need to use install HipChat in another network / hosting (such as Amazon), the VPN is the best option (you have many possibilities (like enable BGP) depending of what firewall/VPNserver you are using).
Otherwise, if you are planning to setup this between your offices you can setup this without a VPN software using MPLS connection, fibre channel (it depends of your infrastructure).
Earlier this year we made the difficult decision to discontinue our team messaging tools, Stride and Hipchat. The end of life date for Stride and Hipchat Cloud is quickly approaching - February 15, 2...
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