cp-smtp-cluster-hz2.hornetsecurity.com IXFR zone transfer

Changes since SOA version

IXFR is a zone transfer request that returns changes since a specific SOA version. Enter the SOA version to request changes since then.

Not an apex domain The domain cp-smtp-cluster-hz2.hornetsecurity.com is not the root of its zone.
Instead, try zone transfer on hornetsecurity.com .