---
title: "zone example.com/IN: refresh: failure trying primary 1.2.3.4#53 errors"
slug: "aa-00282"
description: "How to troubleshoot communication issues between primary and secondary authoritative servers."
tags: ["errors", "authoritative", "logs"]
updated: 2021-07-01T18:17:30Z
published: 2021-07-01T18:17:31Z
---

> ## Documentation Index
> Fetch the complete documentation index at: https://kb.isc.org/llms.txt
> Use this file to discover all available pages before exploring further.

# I get warning messages like "zone example.com/IN: refresh: failure trying primary 1.2.3.4#53: timed out".

Check that you can make UDP queries from the secondary to the primary:

```
dig +norec example.com soa @1.2.3.4
```

You could be generating queries faster than the secondary can cope with. One simple strategy would be to lower the serial query rate:

```
serial-query-rate 5; // default 20
```

Changes to serial-query-rate and other configuration options relating to zone refresh
 BIND has been updated to separate the rate limiting controlled originally by the serial-query-rate into several options, so that SOA refresh queries and zone update notifications can be independently controlled. For more information, see [serial-query-rate, notify-rate and startup-notify-rate: how they impact zone transfers in different versions of BIND](https://kb.isc.org/docs/aa-01313).

                         

DNS system administrators who would like to learn more about tuning their primary and secondary servers more effectively may be interested in reading: [Tuning your BIND configuration effectively for zone transfers (particularly with many frequently-updated zones)](https://kb.isc.org/docs/aa-00726).