When using Genius Vision NVR software, if encounter server unreachable situation, how can one access video footage?
Genius Vision NVR software is based on client/server architecture. This means if server becomes unreachable, you wouldn't be able to do much from client local side, because most recording functions are performed at server.
If you need to recover whatever video data that was on the server, you will need physical access to the hard drive of the server. For this topic, please refer to "How to retrieve/transfer recorded video files" for more information.