refactor(cookie): Warning message when boot with default Erlang cookie

bin/emqx

@@ -537,9 +537,13 @@ if [ -z "$COOKIE" ]; then
     fi
 fi
 
-if [ -z "$COOKIE" ]; then
+[ -z "$COOKIE" ] && COOKIE="$EMQX_DEFAULT_ERLANG_COOKIE"
+if [ $IS_BOOT_COMMAND = 'yes' ] && [ "$COOKIE" = "$EMQX_DEFAULT_ERLANG_COOKIE" ]; then
+    echoerr "!!!!!!"
+    echoerr "WARNING: Default (insecure) Erlang cookie is in use."
     echoerr "Please set node.cookie in $RUNNER_ETC_DIR/emqx.conf or override from environment variable EMQX_NODE_COOKIE"
-    exit 1
+    echoerr "NOTE: Use the same config value for all nodes in the cluster."
+    echoerr "!!!!!!"
 fi
 
 cd "$ROOTDIR"

data/emqx_vars

@@ -14,6 +14,10 @@ RUNNER_DATA_DIR="{{ runner_data_dir }}"
 RUNNER_USER="{{ runner_user }}"
 EMQX_DESCRIPTION='{{ emqx_description }}'
 
+## Do not change EMQX_DEFAULT_ERLANG_COOKIE.
+## Configure EMQX_NODE_COOKIE instead
+EMQX_DEFAULT_ERLANG_COOKIE='{{ emqx_default_erlang_cookie }}'
+
 ## 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"

rebar.config.erl

@@ -203,18 +203,23 @@ overlay_vars(RelType, PkgType, false) ->
     overlay_vars_rel(RelType) ++ overlay_vars_pkg(PkgType).
 
 %% vars per release type, cloud or edge
-overlay_vars_rel(RelType) ->
-    VmArgs = case RelType of
-                 cloud -> "vm.args";
-                 edge -> "vm.args.edge"
-             end,
-    [ {enable_plugin_emqx_rule_engine, RelType =:= cloud}
+overlay_vars_rel(cloud) ->
+    [ {vm_args_file, "vm.args"}
+    | overlay_vars_rel_common(cloud)
+    ];
+overlay_vars_rel(edge) ->
+    [ {vm_args_file, "vm.args.edge"}
+    | overlay_vars_rel_common(edge)
+    ].
+
+overlay_vars_rel_common(RelType) ->
+    [ {emqx_default_erlang_cookie, "emqxsecretcookie"}
+    , {enable_plugin_emqx_rule_engine, RelType =:= cloud}
     , {enable_plugin_emqx_bridge_mqtt, RelType =:= edge}
     , {enable_plugin_emqx_modules, false} %% modules is not a plugin in ce
     , {enable_plugin_emqx_recon, true}
     , {enable_plugin_emqx_retainer, true}
     , {enable_plugin_emqx_telemetry, true}
-    , {vm_args_file, VmArgs}
     ].
 
 %% vars per packaging type, bin(zip/tar.gz/docker) or pkg(rpm/deb)