coredns/middleware/secondary/README.md

secondary

secondary enables serving a zone retrieved from a primary server.

Syntax

secondary [zones...]

• zones zones it should be authoritative for. If empty, the zones from the configuration block are used. Note that without a remote address to get the zone from, the above is not that useful.

A working syntax would be:

secondary [zones...] {
    transfer from address
    [transfer to address]
}

• transfer from specifies from which address to fetch the zone. It can be specified multiple times; if one does not work, another will be tried.
• transfer to can be enabled to allow this secondary zone to be transferred again.

Examples

secondary [zones...] {
    transfer from 10.0.1.1
    transfer from 10.1.2.1
}