19.6. Common Mistakes to Avoid
It is very common for beginners to make mistakes when editing BIND configuration files. Be sure to avoid the following issues:
- Take care to increment the serial number when editing a zone file.If the serial number is not incremented, the master nameserver has the correct, new information, but the slave nameservers are never notified of the change and do not attempt to refresh their data of that zone.
- Be careful to use ellipses and semi-colons correctly in the
/etc/named.conffile.An omitted semi-colon or unclosed ellipse section can cause
namedto refuse to start.
- Remember to place periods (
.) in zone files after all FQDNs and omit them on hostnames.A period at the end of a domain name denotes a fully qualified domain name. If the period is omitted, then
namedappends the name of the zone or the
$ORIGINvalue to complete it.
- If a firewall is blocking connections from the
nameddaemon to other nameservers, the recommended best practice is to change the firewall settings whenever possible. For important security information regarding fixed UDP source ports, refer to Section 22.214.171.124, “Firewall Blocking Communication”