From 4b6f275a438210ac2b1fab41fb41b551cde959c0 Mon Sep 17 00:00:00 2001
From: Shawn <506895667@qq.com>
Date: Wed, 13 Jul 2022 20:14:20 +0800
Subject: [PATCH] fix: emqx start failed after uninstalling old version

---
 bin/emqx       |  4 ++++
 data/emqx_vars | 12 +++++-------
 2 files changed, 9 insertions(+), 7 deletions(-)

diff --git a/bin/emqx b/bin/emqx
index 7eed9ab3c..d6ce86e10 100755
--- a/bin/emqx
+++ b/bin/emqx
@@ -8,6 +8,10 @@ RUNNER_ROOT_DIR="$(cd "$(dirname "$(readlink "$0" || echo "$0")")"/..; pwd -P)"
 # shellcheck disable=SC1090
 . "$RUNNER_ROOT_DIR"/releases/emqx_vars
 
+EMQX_LICENSE_CONF=''
+REL_NAME="emqx"
+ERTS_PATH="$RUNNER_ROOT_DIR/erts-$ERTS_VSN/bin"
+
 RUNNER_SCRIPT="$RUNNER_BIN_DIR/$REL_NAME"
 CODE_LOADING_MODE="${CODE_LOADING_MODE:-embedded}"
 REL_DIR="$RUNNER_ROOT_DIR/releases/$REL_VSN"
diff --git a/data/emqx_vars b/data/emqx_vars
index a872da03a..8ca6bf22d 100644
--- a/data/emqx_vars
+++ b/data/emqx_vars
@@ -12,12 +12,10 @@ RUNNER_LIB_DIR="{{ runner_lib_dir }}"
 RUNNER_ETC_DIR="{{ runner_etc_dir }}"
 RUNNER_DATA_DIR="{{ runner_data_dir }}"
 RUNNER_USER="{{ runner_user }}"
+EMQX_DESCRIPTION='{{ emqx_description }}'
 
-EMQX_LICENSE_CONF=''
-export EMQX_DESCRIPTION='{{ emqx_description }}'
+## Warning: DO NOT create new variables using the above vars in this file,
+## as the vars above can be overwritten by the relup scripts later, like:
+## REL_VSN="new_version"
 
-## computed vars
-REL_NAME="emqx"
-ERTS_PATH="$RUNNER_ROOT_DIR/erts-$ERTS_VSN/bin"
-
-## updated vars here
+## overwritten vars here