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 _a6cbf968fa779d8f6b0b7cfc23ce22f8.ficolo-vcenter6.mgmt.fi.ficore.net is not the root of its zone.
Instead, try zone transfer on comodoca.com .
Instead, try zone transfer on comodoca.com .