当我安装一个像“git-plugin”这样的 jenkins-plugin 时，jenkins 会将我的请求重定向到镜像ftp.halifax.rwth-aachen.de。但我在公司代理后面工作，该代理禁止请求包含“ftp”一词的 URL。
为 jenkins 下载插件时，有没有办法选择或禁用镜像？Jenkins 从不包含“ftp”的站点安装插件没有问题。
这是詹金斯日志视图中的错误：
Dez 22, 2016 3:46:54 PM INFORMATION hudson.model.UpdateCenter$DownloadJob run
Starting the installation of Git client plugin on behalf of admin-ci
Dez 22, 2016 3:46:54 PM SCHWERWIEGEND hudson.model.UpdateCenter$DownloadJob run
Failed to install Git client plugin
hudson.util.IOException2: Failed to download from http://updates.jenkins-ci.org/download/plugins/git-client/2.1.0/git-client.hpi (redirected to: http://ftp.halifax.rwth-aachen.de/jenkins/plugins/git-client/2.1.0/git-client.hpi)
at hudson.model.UpdateCenter$UpdateCenterConfiguration.download(UpdateCenter.java:1169)
at hudson.model.UpdateCenter$DownloadJob._run(UpdateCenter.java:1666)
at hudson.model.UpdateCenter$InstallationJob._run(UpdateCenter.java:1864)
at hudson.model.UpdateCenter$DownloadJob.run(UpdateCenter.java:1640)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at hudson.remoting.AtmostOneThreadExecutor$Worker.run(AtmostOneThreadExecutor.java:110)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.io.IOException: Server returned HTTP response code: 403 for …