diff --git a/docs/developer_guides/appendix_a_basic_components.md b/docs/developer_guides/appendix_a_basic_components.md
index 8e6813c577..78b392b124 100644
--- a/docs/developer_guides/appendix_a_basic_components.md
+++ b/docs/developer_guides/appendix_a_basic_components.md
@@ -57,7 +57,7 @@ type TimeTickProvider interface {
 #### A.2 Session
 ###### ServerID
 
-The ID is stored in a key-value pair on etcd. The key is metaRootPath + "/services/ServerID". The initial value is 0. When a service is registered, it is incremented by 1 and returned to the next registered service.
+The ID is stored in a key-value pair on etcd. The key is metaRootPath + "/session/id". The initial value is 0. When a service is registered, it is incremented by 1 and returned to the next registered service.
 
 ###### Registration