diff --git a/docs/sources/img/installation-datasource_config.png b/docs/sources/img/installation-datasource_config.png
index e677be1..f5ee615 100644
--- a/docs/sources/img/installation-datasource_config.png
+++ b/docs/sources/img/installation-datasource_config.png
@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:2a0416ac20486db595be1139671679fc7177e59644f0131027f4843bfa806d71
-size 141448
+oid sha256:6b58742637f58519a5fab038db0c15b5525d1d330fe5e4a1de954b72f4f1cc3e
+size 225446
diff --git a/docs/sources/installation/configuration.md b/docs/sources/installation/configuration.md
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--- a/docs/sources/installation/configuration.md
+++ b/docs/sources/installation/configuration.md
@@ -34,19 +34,29 @@ Direct access is still supported because in some cases it may be useful to acces
 ### Zabbix API details
 
 - **User** and **Password**: setup login for access to Zabbix API. Also check user's permissions
-in Zabbix if you can't get any groups and hosts in Grafana.
+    in Zabbix if you can't get any groups and hosts in Grafana.
 - **Trends**: enable if you use Zabbix 3.x or patch for trends
-support in Zabbix 2.x ([ZBXNEXT-1193](https://support.zabbix.com/browse/ZBXNEXT-1193)). This option
-strictly recommended for displaying long time periods (more than few days, depending of your item's
-updating interval in Zabbix) because few days of item history contains tons of points. Using trends
-will increase Grafana performance.
-    - **Use trends from**: time after which trends will be used. Default is **7d** (7 days).
-    You can set the time in Grafana format. Valid time specificators are:
+    support in Zabbix 2.x ([ZBXNEXT-1193](https://support.zabbix.com/browse/ZBXNEXT-1193)). This option
+    strictly recommended for displaying long time periods (more than few days, depending of your item's
+    updating interval in Zabbix) because few days of item history contains tons of points. Using trends
+    will increase Grafana performance.
+    - **After**: time after which trends will be used. 
+        Best practice is to set this value to your history storage period (7d, 30d, etc). Default is **7d** (7 days).
+        You can set the time in Grafana format. Valid time specificators are:
         - **h** - hours
         - **d** - days
         - **M** - months
-- **Cache update interval**: plugin caches some api requests for increasing performance. Set this
-value to desired cache lifetime (this option affect data like items list).
+    - **Range**: Time range width after which trends will be used instead of history.
+        It's better to set this value in range of 4 to 7 days to prevent loading large amount of history data.
+        Default is 4 days.
+- **Cache TTL**: plugin caches some api requests for increasing performance. Set this
+    value to desired cache lifetime (this option affect data like items list).
+
+### Alerting
+- **Enable alerting**: enable limited alerting support.
+- **Add thresholds**: get thresholds info from zabbix triggers and add it to graphs.
+    For example, if you have trigger `{Zabbix server:system.cpu.util[,iowait].avg(5m)}>20`, threshold will be set to 20.
+- **Min severity**: minimum trigger severity for showing alert info (OK/Problem).
 
 Then click _Add_ - datasource will be added and you can check connection using 
 _Test Connection_ button. This feature can help to find some mistakes like invalid user name