This documentation is archived and is not being maintained.

Dns.GetHostByName Method

Note: This API is now obsolete.

Gets the DNS information for the specified DNS host name.

Namespace:  System.Net
Assembly:  System (in System.dll)

[<ObsoleteAttribute("GetHostByName is obsoleted for this type, please use GetHostEntry instead.")>]
static member GetHostByName : 
        hostName:string -> IPHostEntry 


Type: System.String
The DNS name of the host.

Return Value

Type: System.Net.IPHostEntry
An IPHostEntry object that contains host information for the address specified in hostName.


hostName is a null reference (Nothing in Visual Basic).


The length of hostName is greater than 255 characters.


An error is encountered when resolving hostName.

The GetHostByName method queries the Internet DNS server for host information. If you pass an empty string as the host name, this method retrieves the standard host name for the local computer.

For asynchronous access to DNS information, use the BeginGetHostByName and EndGetHostByName methods.

If the Ipv6Element.Enabled property is set to true, the Aliases property of the IPHostEntry instance returned is not populated by this method and will always be empty.


This member emits trace information when you enable network tracing in your application. For more information, see Network Tracing.

The following example uses the GetHostByName method to get the DNS information for the specified DNS host name.

No code example is currently available or this language may not be supported.

.NET Framework

Supported in: 1.1, 1.0
Obsolete (compiler warning) in 4
Obsolete (compiler warning) in 3.5
Obsolete (compiler warning) in 3.5 SP1
Obsolete (compiler warning) in 3.0
Obsolete (compiler warning) in 3.0 SP1
Obsolete (compiler warning) in 3.0 SP2
Obsolete (compiler warning) in 2.0
Obsolete (compiler warning) in 2.0 SP1
Obsolete (compiler warning) in 2.0 SP2

.NET Framework Client Profile

Obsolete (compiler warning) in 4
Obsolete (compiler warning) in 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.