Document group limits.

diff --git a/doc/markdown/configuration/metrics.md b/doc/markdown/configuration/metrics.md
index d55f5de196565176f27b65696ea32d4da99beb8c..48fe55365e6d765523e68ce5ae09444280a72bc0 100644 (file)
--- a/doc/markdown/configuration/metrics.md
+++ b/doc/markdown/configuration/metrics.md
@@ -115,4 +115,36 @@ symbol {
 }
 ~~~
 
-A single metric can contain multiple symbols definitions.
\ No newline at end of file
+A single metric can contain multiple symbols definitions.
+
+
+## Symbol groups
+
+Symbols can be grouped to specify their common functionality. For example, one might group all
+`RBL` symbols all together. Moreover, from rspamd 0.9 it is possible to specify group score limit,
+which could be useful, for instance if some specific group should not unconditionally send a message
+to `spam` class. Here is an example of such a functionality:
+
+~~~nginx
+metric {
+       name = default;
+       
+       group {
+               name = "RBL group";
+               max_score = 6.0;
+               
+               symbol {
+                       name = "RBL1";
+                       weight = 1;
+               }
+               symbol {
+                       name = "RBL2";
+                       weight = 4;
+               }
+               symbol {
+                       name = "RBL3";
+                       weight = 5;
+               }
+       }
+}
+~~~
\ No newline at end of file