少于1分钟
https://nginx.org/en/docs/stream/ngx_stream_return_module.html
The ngx_stream_return_module
module (1.11.2) allows sending a specified value to the client and then closing the connection.
server {
listen 12345;
return $time_iso8601;
}
Syntax:return value;
Default: —
Context: server
Specifies a value
to send to the client. The value can contain text, variables, and their combination.