To my knowledge, the only way to do that is to get married to one certain brand of product. Still, from what i have seen, even if you do this, there is usually a limit (16-32) of cameras you can put on there if you provide your own server. If you have multiple sites (13 servers for 100 cameras?? - Are you sure that is right), you could deploy the manufactures NVR appliances. (Some vendors that come to mind include ACTI and Vivotek). You could also go to a full edge recording topology (Axis and Bosch have SDXC storage with client software - not sure if there is a limit to the cameras - Bosch and their new Alliance series are very competitive). Of course, it is not know how you plan to use this (how many end users, mobile access via smartphone, storage duration, etc).
Note: Not sure if Zoneminder is still around and supported but the open source community worked on that for years. Free and unlimited cameras. Could also virtualize (13 servers) and run it with VMWare.