C# 在单独的 DNS 服务器上获取远程计算机的 IP

Question

我正在开发一个实用程序，用于管理指定目录根目录中指定域（不一定是运行应用程序的计算机所在的域）中的多台计算机。我遇到的问题是，一旦我从外部 AD OU 收集了计算机名称，由于 DNS，我无法根据计算机名称进行管理。如果提供了 DNS 服务器的 IP 和该域的凭据，是否可以在外部 DNS 服务器上执行 DNS 查找？

这是我用于初始化过程的代码（在同一域内工作）。非常感谢任何意见！

private Task InitializeComputers()
{
    try
    {
        Computers.Clear();
        object cLock = new object();

        PrincipalContext context = new PrincipalContext(ContextType.Domain, CurrentConfiguration.LDAPAddress, 
            CurrentConfiguration.DirectoryRoot, ContextOptions.Negotiate, 
            CurrentConfiguration.AdminUser, CurrentConfiguration.AdminPassword);

        ComputerPrincipal computer = new ComputerPrincipal(context);

        computer.Name = "*";

        PrincipalSearcher searcher = new PrincipalSearcher(computer);

        PrincipalSearchResult<Principal> result = searcher.FindAll();

        Parallel.ForEach(result, (r) =>
        {
            ComputerPrincipal principal = r as ComputerPrincipal;

            DirectoryObject cObject = new DirectoryObject(CurrentConfiguration)
            {
                Name = principal.Name
            };

            lock (cLock)
            {
                Computers.Add(cObject);
            }
        });

    }
    ... // Catch stuff here
}

private async Task InitializeConnections()
{
    Task[] tasks = Computers.Select(x => x.CheckConnectionAsync()).ToArray();
    await Task.WhenAll(tasks);
}

// This is where I need to be able to get the IP Address. Thoughts???
public Task CheckConnectionAsync()
{
    return Task.Run(() =>
    {
        try
        {
            Ping PingCheck = new Ping();
            PingReply Reply = PingCheck.Send(Name); // <--- need IP Address instead

            if (Reply.Status == IPStatus.Success)
            {
                IsAvailable = true;
                IPHostEntry host = Dns.GetHostEntry(Name); // Does not work for machines on different domain.
                IPAddress = host.AddressList.FirstOrDefault().ToString();
            }
            else
            {
                IsAvailable = false;
                IsWMIActive = false;
            }
        }
        ... // catch stuff here ...
    });
}

Answer 1

跟进，我找到的解决方案来自Heijden's DNS Resolver。我编写了一个简单的 DnsManager 类，其中包含一个静态 GetIPAddress 方法，用于从 A 记录中提取 IP。

public static string GetIPAddress(string name)
{
    Resolver resolver = new Resolver();
    resolver.DnsServer = ((App)App.Current).CurrentConfiguration.DNSAddress;
    resolver.Recursion = true;
    resolver.Retries = 3;
    resolver.TimeOut = 1;
    resolver.TranportType = TransportType.Udp;

    Response response = resolver.Query(name, QType.A);

    if (response.header.ANCOUNT > 0)
    {
         return ((AnswerRR)response.Answer[0]).RECORD.ToString();
    }

    return null;
}

那么，更新后的 CheckConnectionAsync 方法现在写成这样：

public Task CheckConnectionAsync()
{
    return Task.Run(() =>
    {
        try
        {
             IPAddress = DnsManager.GetIPAddress(Name + "." + CurrentConfig.DomainName);
             ... // check availability by IP rather than name...
        }
        // catch stuff here...
    });
}

Answer 2

一旦您计划将专用服务器作为 DNS 源进行查询，您就必须远离默认库。在调查专用 DNS 请求后，我尝试了这个（如果没记错的话）： http://www.codeproject.com/Articles/12072/C-NET-DNS-query-component