Azure Web作业 "Could not create SSL/TLS secure channel"

Question

我有一个 Azure WebJob，在本地运行时工作正常，但在 Azure 中运行时会引发异常。 WebJob 正在通过 HTTPS 进行外部调用，这在 Azure 中会产生以下异常:

System.Net.WebException: The request was aborted: Could not create SSL/TLS secure channel. at System.Net.HttpWebRequest.GetResponse()

我还尝试使用 ServicePointManager 将安全协议(protocol)设置为 TLS，但这也对异常没有影响。这是我的代码片段。

ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls | SecurityProtocolType.Tls11 | SecurityProtocolType.Tls12;

var request = (HttpWebRequest)WebRequest.Create(url);
                request.Method = "GET";

Azure 是否阻止 WebJobs 访问 Internet，还是我做错了什么？

Answer 1

我遇到了同样的问题，最终在 MSDN 论坛上的以下帖子的帮助下成功解决了问题:

https://social.msdn.microsoft.com/Forums/en-US/ca6372be-3169-4fb5-870f-bfbea605faf6/azure-webapp-webjob-exception-could-not-create-ssltls-secure-channel?forum=windowsazurewebsitespreview

似乎 Microsoft 上个月(2015 年 10 月)针对此问题部署了修复程序，但我还必须设置:

ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12 | SecurityProtocolType.Tls11;

请注意，我遗漏了 SecurityProtocol.Tls，因为它似乎不受 Microsoft 员工在 MSDN 主题的回复之一中提到的支持:

The client hello from .NET code running inside a web app shows that it is trying to use TLS v1.0 with TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA, TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA ciphers that are obviously not supported on the server. In .NET 4.5 you can ask it to use a different protocol version and then things start working for me once I do that.