Check duplicate when creating ALIAS records
When creating a ALIAS record, it should be checked that there is no duplicate A/AAAA/CNAME/DNAME record. For those 4, it should also be checked if there is a ALIAS record with the same hostname.
When creating a ALIAS record, it should be checked that there is no duplicate A/AAAA/CNAME/DNAME record. For those 4, it should also be checked if there is a ALIAS record with the same hostname.