Index: documentation/src/main/resources/pages/ditto/installation-operating.md
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
diff --git a/documentation/src/main/resources/pages/ditto/installation-operating.md b/documentation/src/main/resources/pages/ditto/installation-operating.md
--- a/documentation/src/main/resources/pages/ditto/installation-operating.md	(revision cde6c87a6ac7e2804d8c9efde8570e2c5114a3da)
+++ b/documentation/src/main/resources/pages/ditto/installation-operating.md	(revision 93a029d8e13658359180696bc466d9c5298613d0)
@@ -612,10 +612,10 @@
       custom-metrics {
         ...
       }
-      custom-aggregate-metrics {
+      custom-aggregation-metrics {
         online_status {
           enabled = true
-          scrape-interval = 1m # override scrape interval, run every 20 minute
+          scrape-interval = 20m # override scrape interval, run every 20 minutes
           namespaces = [
             "org.eclipse.ditto"
           ]
@@ -628,6 +628,7 @@
             "health" = "{{ inline:health }}"
             "hardcoded-tag" = "hardcoded_value"
             "location" = "{{ group-by:location | fn:default('missing location') }}"
+            "isGateway" = "{{ group-by:isGateway }}"
           }
           filters {
             online_filter {
@@ -654,19 +655,19 @@
 
 To add custom metrics via System properties, the following example shows how the above metric can be configured:
 ```
--Dditto.search.operator-metrics.custom-search-metrics.online_status.enabled=true
--Dditto.search.operator-metrics.custom-search-metrics.online_status.scrape-interval=20m
--Dditto.search.operator-metrics.custom-search-metrics.online_status.namespaces.0=org.eclipse.ditto
--Dditto.search.operator-metrics.custom-search-metrics.online_status.tags.online="{{online_placeholder}}"
--Dditto.search.operator-metrics.custom-search-metrics.online_status.tags.location="{{attributes/Info/location}}"
+-Dditto.search.operator-metrics.custom-aggregation-metrics.online_status.enabled=true
+-Dditto.search.operator-metrics.custom-aggregation-metrics.online_status.scrape-interval=20m
+-Dditto.search.operator-metrics.custom-aggregation-metrics.online_status.namespaces.0=org.eclipse.ditto
+-Dditto.search.operator-metrics.custom-aggregation-metrics.online_status.tags.online="{{online_placeholder}}"
+-Dditto.search.operator-metrics.custom-aggregation-metrics.online_status.tags.location="{{attributes/Info/location}}"
 
--Dditto.search.operator-metrics.custom-search-metrics.online_status.filters.online-filter.filter=gt(features/ConnectionStatus/properties/status/readyUntil/,time:now)
--Dditto.search.operator-metrics.custom-search-metrics.online_status.filters.online-filter.inline-placeholder-values.online_placeholder=true
--Dditto.search.operator-metrics.custom-search-metrics.online_status.filters.online-filter.fields.0=attributes/Info/location
+-Dditto.search.operator-metrics.custom-aggregation-metrics.online_status.filters.online-filter.filter=gt(features/ConnectionStatus/properties/status/readyUntil/,time:now)
+-Dditto.search.operator-metrics.custom-aggregation-metrics.online_status.filters.online-filter.inline-placeholder-values.online_placeholder=true
+-Dditto.search.operator-metrics.custom-aggregation-metrics.online_status.filters.online-filter.fields.0=attributes/Info/location
 
--Dditto.search.operator-metrics.custom-search-metrics.online_status.filters.offline-filter.filter=lt(features/ConnectionStatus/properties/status/readyUntil/,time:now)
--Dditto.search.operator-metrics.custom-search-metrics.online_status.filters.offline-filter.inline-placeholder-values.online_placeholder=false
--Dditto.search.operator-metrics.custom-search-metrics.online_status.filters.offline-filter.fields.0=attributes/Info/location
+-Dditto.search.operator-metrics.custom-aggregation-metrics.online_status.filters.offline-filter.filter=lt(features/ConnectionStatus/properties/status/readyUntil/,time:now)
+-Dditto.search.operator-metrics.custom-aggregation-metrics.online_status.filters.offline-filter.inline-placeholder-values.online_placeholder=false
+-Dditto.search.operator-metrics.custom-aggregation-metrics.online_status.filters.offline-filter.fields.0=attributes/Info/location
 
 ```
 
@@ -679,6 +680,7 @@
 ```
 online_status{location="Berlin",online="false"} 6.0
 online_status{location="Immenstaad",online="true"} 8.0
+```
 
 ## Tracing
 
Index: thingsearch/service/src/main/java/org/eclipse/ditto/thingsearch/service/starter/actors/OperatorSearchMetricsProviderActor.java
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
diff --git a/thingsearch/service/src/main/java/org/eclipse/ditto/thingsearch/service/starter/actors/OperatorSearchMetricsProviderActor.java b/thingsearch/service/src/main/java/org/eclipse/ditto/thingsearch/service/starter/actors/OperatorSearchMetricsProviderActor.java
--- a/thingsearch/service/src/main/java/org/eclipse/ditto/thingsearch/service/starter/actors/OperatorSearchMetricsProviderActor.java	(revision cde6c87a6ac7e2804d8c9efde8570e2c5114a3da)
+++ b/thingsearch/service/src/main/java/org/eclipse/ditto/thingsearch/service/starter/actors/OperatorSearchMetricsProviderActor.java	(revision 93a029d8e13658359180696bc466d9c5298613d0)
@@ -85,7 +85,7 @@
         this.customSearchMetricConfigMap = searchConfig.getOperatorMetricsConfig().getCustomAggregationMetricConfigs();
         this.metricsGauges = new HashMap<>();
         this.inlinePlaceholderResolvers = new HashMap<>();
-        this.customSearchMetricsGauge = KamonGauge.newGauge("custom-search-metrics-count-of-instruments");
+        this.customSearchMetricsGauge = KamonGauge.newGauge("custom-aggregation-metrics-count-of-instruments");
         this.customSearchMetricConfigMap.forEach((metricName, customSearchMetricConfig) -> {
             initializeCustomMetricTimer(metricName, customSearchMetricConfig,
                     getMaxConfiguredScrapeInterval(searchConfig.getOperatorMetricsConfig()));
Index: thingsearch/service/src/main/resources/search-dev.conf
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
diff --git a/thingsearch/service/src/main/resources/search-dev.conf b/thingsearch/service/src/main/resources/search-dev.conf
--- a/thingsearch/service/src/main/resources/search-dev.conf	(revision cde6c87a6ac7e2804d8c9efde8570e2c5114a3da)
+++ b/thingsearch/service/src/main/resources/search-dev.conf	(revision 93a029d8e13658359180696bc466d9c5298613d0)
@@ -32,32 +32,25 @@
           namespaces = [
             "org.eclipse.ditto"
           ]
-          group-by:{
+          group-by {
             "location" = "attributes/Info/location"
             "isGateway" = "attributes/Info/gateway"
           }
-          tags: {
+          tags {
             "online" = "{{ inline:online_placeholder }}"
             "health" = "{{ inline:health }}"
             "hardcoded-tag" = "value"
             "location" = "{{ group-by:location | fn:default('missing location') }}"
             "isGateway" = "{{ group-by:isGateway }}"
           }
-          filters = {
-            online_filter = {
+          filters {
+            online_filter {
               filter = "gt(features/ConnectionStatus/properties/status/readyUntil/,time:now)"
-              inline-placeholder-values = {
+              inline-placeholder-values {
                 "online_placeholder" = true
                 "health" = "good"
               }
             }
-            offline_filter = {
-              filter = "lt(features/ConnectionStatus/properties/status/readyUntil/,time:now)"
-              inline-placeholder-values = {
-                "online_placeholder" = false
-                "health" = "bad"
-              }
-            }
           }
         }
       }
Index: thingsearch/service/src/test/java/org/eclipse/ditto/thingsearch/service/common/config/DefaultCustomAggregationMetricConfigTest.java
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
diff --git a/thingsearch/service/src/test/java/org/eclipse/ditto/thingsearch/service/common/config/DefaultCustomAggregationMetricConfigTest.java b/thingsearch/service/src/test/java/org/eclipse/ditto/thingsearch/service/common/config/DefaultCustomAggregationMetricConfigTest.java
--- a/thingsearch/service/src/test/java/org/eclipse/ditto/thingsearch/service/common/config/DefaultCustomAggregationMetricConfigTest.java	(revision cde6c87a6ac7e2804d8c9efde8570e2c5114a3da)
+++ b/thingsearch/service/src/test/java/org/eclipse/ditto/thingsearch/service/common/config/DefaultCustomAggregationMetricConfigTest.java	(revision 93a029d8e13658359180696bc466d9c5298613d0)
@@ -39,7 +39,7 @@
     @BeforeClass
     public static void initTestFixture() {
         config = ConfigFactory.load("custom-search-metric-test");
-        customSearchMetricTestConfig = config.getConfig("ditto.search.operator-metrics.custom-search-metrics");
+        customSearchMetricTestConfig = config.getConfig("ditto.search.operator-metrics.custom-aggregation-metrics");
     }
 
     @Test
Index: thingsearch/service/src/test/resources/custom-search-metric-test.conf
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
diff --git a/thingsearch/service/src/test/resources/custom-search-metric-test.conf b/thingsearch/service/src/test/resources/custom-search-metric-test.conf
--- a/thingsearch/service/src/test/resources/custom-search-metric-test.conf	(revision cde6c87a6ac7e2804d8c9efde8570e2c5114a3da)
+++ b/thingsearch/service/src/test/resources/custom-search-metric-test.conf	(revision 93a029d8e13658359180696bc466d9c5298613d0)
@@ -36,7 +36,7 @@
       scrape-interval = ${?THINGS_SEARCH_OPERATOR_METRICS_SCRAPE_INTERVAL}
       custom-metrics {
       }
-      custom-search-metrics {
+      custom-aggregation-metrics {
         online_status {
           enabled = true
           scrape-interval = 1m # override scrape interval, run every 20 minute
@@ -53,7 +53,7 @@
             "health" = "{{ inline:health }}"
             "hardcoded-tag" = "value"
             "location" = "{{ group-by:location | fn:default('missing location') }}"
-            "altitude" = "{{ group-by:isGateway }}"
+            "isGateway" = "{{ group-by:isGateway }}"
           }
           filters = {
             online_filter = {