Description

The auto plugin is used for an “old-style” DNS server. It serves from a preloaded file that exists on disk. If the zone file contains signatures (i.e. is signed, i.e. using DNSSEC) correct DNSSEC answers are returned. Only NSEC is supported! If you use this setup you are responsible for re-signing the zonefile. New or changed zones are automatically picked up from disk only when SOA’s serial changes. If the zones are not updated via a zone transfer, the serial must be manually changed.

Syntax

auto [ZONES...] {
    directory DIR [REGEXP ORIGIN_TEMPLATE]
    reload DURATION
}

ZONES zones it should be authoritative for. If empty, the zones from the configuration block are used.

• directory loads zones from the specified DIR. If a file name matches REGEXP it will be used to extract the origin. ORIGIN_TEMPLATE will be used as a template for the origin. Strings like {<number>} are replaced with the respective matches in the file name, e.g. {1} is the first match, {2} is the second. The default is: db\.(.*) {1} i.e. from a file with the name db.example.com, the extracted origin will be example.com. REGEXP must not be longer than 10000 characters.
• reload interval to perform reloads of zones if SOA version changes and zonefiles. It specifies how often CoreDNS should scan the directory to watch for file removal and addition. Default is one minute. Value of 0 means to not scan for changes and reload. eg. 30s checks zonefile every 30 seconds and reloads zone when serial changes.

For enabling zone transfers look at the transfer plugin.

All directives from the file plugin are supported. Note that auto will load all zones found, even though the directive might only receive queries for a specific zone. I.e:

. {
    auto example.org {
        directory /etc/coredns/zones
    }
}

Will happily pick up a zone for example.COM, except it will never be queried, because the auto directive only is authoritative for example.ORG.

Examples

Load org domains from /etc/coredns/zones/org and allow transfers to the internet, but send notifies to 10.240.1.1

org {
    auto {
        directory /etc/coredns/zones/org
    }
    transfer {
        to *
        to 10.240.1.1
    }
}

Load org domains from /etc/coredns/zones/org and looks for file names as www.db.example.org, where example.org is the origin. Scan every 45 seconds.

org {
    auto {
        directory /etc/coredns/zones/org www\.db\.(.*) {1}
        reload 45s
    }
}

Also

Use the root plugin to help you specify the location of the zone files. See the transfer plugin to enable outgoing zone transfers.