update doc

README.md

@@ -30,7 +30,11 @@ frp also has a P2P connect mode.
     * [Using Environment Variables](#using-environment-variables)
     * [Dashboard](#dashboard)
     * [Admin UI](#admin-ui)
+    * [Monitor](#monitor)
+        * [Prometheus](#prometheus)
     * [Authenticating the Client](#authenticating-the-client)
+        * [Token Authentication](#token-authentication)
+        * [OIDC Authentication](#oidc-authentication)
     * [Encryption and Compression](#encryption-and-compression)
         * [TLS](#tls)
     * [Hot-Reloading frpc configuration](#hot-reloading-frpc-configuration)
@@ -49,9 +53,10 @@ frp also has a P2P connect mode.
     * [Get Real IP](#get-real-ip)
         * [HTTP X-Forwarded-For](#http-x-forwarded-for)
         * [Proxy Protocol](#proxy-protocol)
-    * [Require HTTP Basic auth (password) for web services](#require-http-basic-auth-password-for-web-services)
-    * [Custom subdomain names](#custom-subdomain-names)
-    * [URL routing](#url-routing)
+    * [Require HTTP Basic Auth (Password) for Web Services](#require-http-basic-auth-password-for-web-services)
+    * [Custom Subdomain Names](#custom-subdomain-names)
+    * [URL Routing](#url-routing)
+    * [TCP Port Multiplexing](#tcp-port-multiplexing)
     * [Connecting to frps via HTTP PROXY](#connecting-to-frps-via-http-proxy)
     * [Range ports mapping](#range-ports-mapping)
     * [Client Plugins](#client-plugins)
@@ -435,6 +440,18 @@ admin_pwd = admin
 
 Then visit `http://127.0.0.1:7400` to see admin UI, with username and password both being `admin` by default.
 
+### Monitor
+
+When dashboard is enabled, frps will save monitor data in cache. It will be cleared after process restart.
+
+Prometheus is also supported.
+
+#### Prometheus
+
+Enable dashboard first, then configure `enable_prometheus = true` in `frps.ini`.
+
+`http://{dashboard_addr}/metrics` will provide prometheus monitor data.
+
 ### Authenticating the Client
 
 There are 2 authentication methods to authenticate frpc with frps. 
@@ -818,11 +835,11 @@ locations = /news,/about
 
 HTTP requests with URL prefix `/news` or `/about` will be forwarded to **web02** and other requests to **web01**.
 
-### TCP Multiplexing
+### TCP Port Multiplexing
 
 frp supports receiving TCP sockets directed to different proxies on a single port on frps, similar to `vhost_http_port` and `vhost_https_port`.
 
-The only supported TCP multiplexing method available at the moment is `httpconnect` - HTTP CONNECT tunnel.
+The only supported TCP port multiplexing method available at the moment is `httpconnect` - HTTP CONNECT tunnel.
 
 When setting `tcpmux_httpconnect_port` to anything other than 0 in frps under `[common]`, frps will listen on this port for HTTP CONNECT requests.