Fast concurrent checking of SOA DNS records for .co.za domains

Question

I want to implement bulk availability checking of .co.za domain names as accurately as possible by checking for the existence of SOA

Answer 1

This would be very easy using JH Software's DNS Client Library for .NET:

var Response = JHSoftware.DnsClient.Lookup("example.com", 
                              JHSoftware.DnsClient.RecordType.SOA);

It also supports BeginLookup / EndLookup methods for asynchronous lookups.