map $http_upgrade $connection_upgrade {
    default upgrade;
    "" close;
}

limit_conn_zone $binary_remote_addr zone=conn_per_ip:20m;
limit_req_zone $binary_remote_addr zone=req_per_ip:20m rate=10r/s;
limit_req_zone $binary_remote_addr zone=auth_per_ip:10m rate=10r/m;