207-172-4-0.in-addr.mail.rcn.net 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 207-172-4-0.in-addr.mail.rcn.net is not the root of its zone.
Instead, try zone transfer on mail.rcn.net .