diff --git a/Filer-Active-Active-xDC-synchronization.md b/Filer-Active-Active-xDC-synchronization.md
index 79c0057..69579c5 100644
--- a/Filer-Active-Active-xDC-synchronization.md
+++ b/Filer-Active-Active-xDC-synchronization.md
@@ -6,7 +6,7 @@ It can run either in Active-Active mode or Active-Passive mode.
 
 # Usage
 
-From any computer, run this command:
+From any computer that can access filer, master and volume serve in both SeaweedFS clusters, run this command:
 
 ```
 # synchronize each cluster