Get All IP Addresses on Machine

Question

How can I get all of the IP addresses attached to the machine that my application (C# NET Console app) is running on? I need to bind a WCF service to the primary IP address, and return a list of the full IP address list.

using System.Net;

string myHostName = Dns.GetHostName().ToString();
string ipAddress = Dns.Resolve(HostName).AddressList[0].ToString();

This is what I am using right now to get the Primary IP address, but I can't figure out how to get the rest to return them.

If I bind a WCF service to localhost:8000, will that expose it on the primary?

Answer 1

Why not just bind to 0.0.0.0 ?
That way you listen on all ips

Answer 2

I think the OP is asking about how to get all addresses on a local NIC, not just those addresses known to DNS. By primary he probably means the main address under "use the following IP address" in the adapter properties, and by "the rest" he probably means those listed in Advanced > (Additional) IP Addesses.

DNS will not necessarily know those.

Answer 3

I think this example should help you.

// Get host name
String strHostName = Dns.GetHostName();

// Find host by name
IPHostEntry iphostentry = Dns.GetHostByName(strHostName);

// Enumerate IP addresses
foreach(IPAddress ipaddress in iphostentry.AddressList)
{
    ....
}

Edit:

"There's no such thing as a "primary" IP address.

The routing table determines which outward-facing IP address is used depending on the destination IP address (and by extension, the network interface, which itself can be virtual or physical)."

Answer 4

The DNS variants work across the network, but one DNS entry can have many IP addresses and one IP address can have many DNS entries. More importantly, an address needn't be bound to a DNS entry at all.

For the local machine try this:-

  foreach (NetworkInterface netInterface in NetworkInterface.GetAllNetworkInterfaces())
  {
    Console.WriteLine("Name: " + netInterface.Name);
    Console.WriteLine("Description: " + netInterface.Description);
    Console.WriteLine("Addresses: ");
    IPInterfaceProperties ipProps = netInterface.GetIPProperties();
    foreach (UnicastIPAddressInformation addr in ipProps.UnicastAddresses)
    {
      Console.WriteLine(" " + addr.Address.ToString());
    }
    Console.WriteLine("");
  }

Answer 5

You should probably bind to 0.0.0.0:8000, that will expose it on all available IP addresses and only bind to a particular IP address if the user/administrator demands so.

Answer 6

IPAddress[] localIPs = Dns.GetHostAddresses(Dns.GetHostName());