Так сейчас:
if ($http_user_agent ~
(uTorrent/2040\(21515\)|ABC/ABC-3\.1\.0|BitTorrent/3\.4\.2|uTorrent/1500|(Azureus
2\.5\.0\.0)|Opera|Presto|Osprey)) {
return 403;
}
Posted at Nginx Forum: http://forum.nginx.org/read.php?21,155300,157700#msg-157700