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 example.org {
transfer from 10.0.1.1
transfer from 10.1.2.1
}