Exporter: Listen at port 9972 for Prometheus exporter.

[chundonglinlin]

Exporter add default port listen for Prometheus. SRS organization applies for the default port(9972) at the official Prometheus address(Default port allocations).You can see prometheus.conf,

listen              1935;
max_connections     1000;
daemon              off;
srs_log_tank        console;
http_api {
    enabled         on;
    listen          1985;
}
http_server {
    enabled         on;
    listen          8080;
}
rtc_server {
    enabled on;
    listen 8000; # UDP port
    # @see https://ossrs.net/lts/zh-cn/docs/v4/doc/webrtc#config-candidate
    candidate $CANDIDATE;
}
# Prometheus exporter config.
exporter {
    enabled         on;
    listen          9972;
    label           cn-beijing;
    tag             cn-edge;
}
vhost __defaultVhost__ {
    hls {
        enabled         on;
    }
    http_remux {
        enabled     on;
        mount       [vhost]/[app]/[stream].flv;
    }
    rtc {
        enabled     on;
        # @see https://ossrs.net/lts/zh-cn/docs/v4/doc/webrtc#rtmp-to-rtc
        rtmp_to_rtc on;
        # @see https://ossrs.net/lts/zh-cn/docs/v4/doc/webrtc#rtc-to-rtmp
        rtc_to_rtmp on;
    }
}