diff --git a/src/http/ngx_http_request.c b/src/http/ngx_http_request.c
index 98cc8c7..0810526 100644
--- a/src/http/ngx_http_request.c
+++ b/src/http/ngx_http_request.c
@@ -849,7 +849,7 @@ ngx_http_ssl_servername(ngx_ssl_conn_t *ssl_conn, int *ad, void *arg)
     servername = SSL_get_servername(ssl_conn, TLSEXT_NAMETYPE_host_name);
 
     if (servername == NULL) {
-        return SSL_TLSEXT_ERR_NOACK;
+        return SSL_TLSEXT_ERR_ALERT_FATAL;
     }
 
     c = ngx_ssl_get_connection(ssl_conn);
@@ -864,7 +864,7 @@ ngx_http_ssl_servername(ngx_ssl_conn_t *ssl_conn, int *ad, void *arg)
     host.len = ngx_strlen(servername);
 
     if (host.len == 0) {
-        return SSL_TLSEXT_ERR_NOACK;
+        return SSL_TLSEXT_ERR_ALERT_FATAL;
     }
 
     host.data = (u_char *) servername;
@@ -879,7 +879,7 @@ ngx_http_ssl_servername(ngx_ssl_conn_t *ssl_conn, int *ad, void *arg)
                                      NULL, &cscf)
         != NGX_OK)
     {
-        return SSL_TLSEXT_ERR_NOACK;
+        return SSL_TLSEXT_ERR_ALERT_FATAL;
     }
 
     hc->ssl_servername = ngx_palloc(c->pool, sizeof(ngx_str_t));