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 ecxamsrtr1-100-221-255-159-am.nfvhost.equinix.com is not the root of its zone.
Instead, try zone transfer on nfvhost.equinix.com .
Instead, try zone transfer on nfvhost.equinix.com .