How to perform “nslookup host server”

Question

My C# service needs to periodically poll nslookup host server. Currently it spawns a Process that executes batch script. Due to perfor

Answer 1

I'm not sure how to do this using the framework directly because I've never needed to use a DNS server different than the one specified in the local machine configuration. But you might want to give this library a try. I've never used it but as far as I can tell it will allow you to specify a DNS server to use in resolving the host name you pass.

Answer 2

I looked into this a while back. It is not possible in the standard class libraries, so you are going to have to use an external component to do this properly.

There are a number of free and paid choices available to you. My implementation was based around a posting on CodeProject, which worked quite well. DNS Client Library for .NET (also mentioned by kprobst) was released after I finished mine, or I would've used this one initially.

Answer 3

The problem was solved!

http://msdn.microsoft.com/en-us/library/ms682016(VS.85).aspx

See "Great Example here" section

[DllImport("dnsapi", EntryPoint="DnsQuery_W", CharSet=CharSet.Unicode, SetLastError=true, ExactSpelling=true)]
private static extern int DnsQuery([MarshalAs(UnmanagedType.VBByRefStr)]ref string pszName, QueryTypes wType, QueryOptions options, int aipServers, ref IntPtr ppQueryResults, int pReserved);
[DllImport("dnsapi", CharSet=CharSet.Auto, SetLastError=true)]
private static extern void DnsRecordListFree(IntPtr pRecordList, int FreeType);

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