From 9c6bb19abd08c3267ab02ddf80e9038de44f6e09 Mon Sep 17 00:00:00 2001
From: mths1 <68608970+mths1@users.noreply.github.com>
Date: Mon, 24 Apr 2023 09:46:54 +0200
Subject: [PATCH] Update introduction.md

---
 monitoring/introduction.md | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/monitoring/introduction.md b/monitoring/introduction.md
index fed4f2f..2a60b64 100644
--- a/monitoring/introduction.md
+++ b/monitoring/introduction.md
@@ -56,3 +56,7 @@ counter.mqtt_connack_sent = 0
 
 All available labels can be show using `vmq-admin metrics show --help`.
 
+{% hint style="warning" %}
+VerneMQ is a implemented in Erlang, which is a highly concurrent system, and follows a fail fast machanism. It might happen that in some scenarios the metrics do not seem to "match". One typcial example is sockets_open and sockets_close. In case of failure, the sockets_close metric might not be increased and thus there is a difference between opened sockets and closed sockets. The metric is nonetheless useful when inspecting the the running system.
+{% endhint %}
+