一、问题描述（Problem Description）：
在jenkins中创建新任务时候选择“拷贝已存在任务”，点击OK，跳转到下一步时候弹出如下错误信息："No valid crumb was included in the request"
jenkins new job -> copy existing job -> click OK -> "No valid crumb was included in the request"
jenkins 填写构建参数，点击“BUILD”，提示： "No valid crumb was included in the request"
二、运行环境（Environment）：
apache + jboss-as-7.1.1.Final，Windows XP SP3，jdk 1.6.0_33
三、错误原因（Reason）：
jenkins在http请求头部中放置了一个名为.crumb的token。在使用了反向代理，并且在jenkins设置中勾选了“防止跨站点请求伪造（Prevent Cross Site Request Forgery exploits）”之后此token会被转发服务器apache/nginx认为是不合法头部而去掉。导致跳转失败。
The problem is that jenkins stores its' csrf token in a http header called '.crumb', AFAIK headers must only contain alphanumerics and dashes, and apache/nginx will remove invalid headers from the request (unless configured not to).
四、解决方案（Solution）：
1.在apache/nginx中设置ignore_invalid_headers，或者：
2.在jenkins全局安全设置中取消勾选“防止跨站点请求伪造（Prevent Cross Site Request Forgery exploits）”。
1.Set ignore_invalid_headers in your apache/nginx server, or:
2.Uncheck "Prevent Cross Site Request Forgery exploits" in jenkins global security settings.
参考资料（References）