Hello,
trying to resolve some relatively simple problem. We have a webserver,
it works NGINX. All the requirements that come with either sent from
this site, or (as have the flv and mp4) to send to another server and
send it from this second server
To use this simple rule in nginx.conf:

if (!-e $request_filename) {
rewrite ^(.*)flv$ http://second-server.cz$1flv;
rewrite ^(.*)mp4$ http://second-server.cz$1mp4;
}

New but need to be directed only to the requirements of this from some
IP ranges (which is about 5000) and everything outside these ranges are
odbavovalo directly from this server.
(the local node in the Czech Republic where the link is cheap providers
from one datacenter, and external flow is cheap from the second
datacenter).

Is there a simple solution to this problem?

Thanks a lot.