diff --git a/src/http/ngx_http_core_module.c b/src/http/ngx_http_core_module.c
index 4f43ead43..c8266a3e8 100644
--- a/src/http/ngx_http_core_module.c
+++ b/src/http/ngx_http_core_module.c
@@ -3172,6 +3172,13 @@ ngx_http_core_server_name(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
                                &value[i]);
         }
 
+        if (value[i].len == 1 && ch == '*') {
+            ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
+                               "\"server_name *\" is unsupported, use "
+                               "\"server_name_in_redirect off\" instead");
+            return NGX_CONF_ERROR;
+        }
+
         sn = ngx_array_push(&cscf->server_names);
         if (sn == NULL) {
             return NGX_CONF_ERROR;