diff --git a/acme.sh b/acme.sh
index ebddf81d..a4224fc9 100755
--- a/acme.sh
+++ b/acme.sh
@@ -2763,9 +2763,9 @@ _isRealNginxConf() {
 
         _left="$(sed -n "${_start_nn},99999p" "$2")"
         _debug2 _left "$_left"
-        if echo "$_left" | tr "\t" ' ' | grep -n "^ *server *" >/dev/null; then
-          _end=$(echo "$_left" | tr "\t" ' ' | grep -n "^ *server *" | _head_n 1)
-          _debug "_end" "$_end"
+        _end="$(echo "$_left" | tr "\t" ' ' | grep -n "^ *server *" | grep -v server_name | _head_n 1)"
+        _debug "_end" "$_end"
+        if [ "$_end" ]; then
           _end_n=$(echo "$_end" | cut -d : -f 1)
           _debug "_end_n" "$_end_n"
           _seg_n=$(echo "$_left" | sed -n "1,${_end_n}p")