diff --git a/conf/nginx/sni_forward.conf b/conf/nginx/sni_forward.conf
index a21786e79..79fb5c7a6 100644
--- a/conf/nginx/sni_forward.conf
+++ b/conf/nginx/sni_forward.conf
@@ -9,7 +9,7 @@ stream {
     }
     
     {% for domain_ip in domain_ip_map %}
-    upstream {{ domain_ip.split(":")[0].replace('.', '') }} {
+    upstream {{ domain_ip.split(":")[0].replace('.', '_') }} {
         server {{ domain_ip.split(":")[1] }}:443;
     }
     {% endfor %}