我们有时无法连接到 Facebook OpenGraph API。我们的 .NET 客户端返回以下错误：
System.Net.WebException: Unable to connect to the remote server ---> System.Net.Sockets.SocketException: 连接尝试失败，因为连接方在一段时间后没有正确响应，或者建立连接失败，因为连接的主机未能在 System.Net.Sockets.Socket.InternalConnect(EndPoint remoteEP) 在 System.Net.ServicePoint.ConnectSocketInternal(Boolean connectFailure, Socket s4, Socket s6, Socket&socket, IPAddress&地址, ConnectSocketState状态, IAsyncResult asyncResult, Int32 timeout, Exception&异常)
请注意，这并不特定于任何特定的 API 调用。
甚至 ping graph.facebook.com 也会随机超时。
以下是一些跟踪路线信息：
1 <1 ms <1 ms <1 ms ip-97-74-87-252.ip.secureserver.net [97.74.87.252]
2 <1 ms <1 ms <1 ms ip-208-109-113-173.ip.secureserver.net [208.109.113.173]
3 1 ms <1 ms <1 ms ip-97-74-252-21.ip.secureserver.net [97.74.252.21]
4 1 ms <1 ms <1 ms ip-97-74-252-21.ip.secureserver.net [97.74.252.21]
5 9 ms 1 ms 1 ms 206-15-85-9.static.twtelecom.net [206.15.85.9]
6 13 ms 13 ms 44 ms lax2-pr2-xe-1-3-0-0.us.twtelecom.net [66.192.241.218]
7 26 ms 28 ms 27 ms cr1.la2ca.ip.att.net [12.122.104.14]
8 26 ms 27 ms 27 ms cr82.sj2ca.ip.att.net [12.122.1.146]
9 23 ms 23 ms 23 ms 12.122.128.201
10 22 ms 22 ms 22 ms 12.249.231.26
11 22 ms 22 ms 22 ms ae1.bb02.sjc1.tfbnw.net [204.15.21.164]
12 23 ms 23 ms 23 ms ae5.dr02.snc4.tfbnw.net [204.15.21.169]
13 24 ms 23 ms 23 ms eth-17-2.csw02b.snc4.tfbnw.net [74.119.76.105]
14 * * * Request timed out.
15 * * * Request timed out.
16 * * * Request timed out.
17 * * * Request timed out.
18 * * * Request timed out.
重现步骤：
- 尝试 ping graph.facebook.com。
- 某些 IP 的 Ping 请求将超时。