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README.md

-## Jenkins 开源镜像站点
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+## Jenkins Update Center Mirror
+
+This repo stores several Jenkins Update Center mirrors.
+Which include:
+
+* tsinghua
+
+The mirror proxy is [https://updates.jenkins-zh.cn/update-center.json](https://updates.jenkins-zh.cn/update-center.json)
+
+## Backup
+
+This repo has been backuped in several places:
+
+* [Gitee](https://jenkins-zh.gitee.io/update-center-mirror/)
+* [GitHub](https://jenkins-zh.github.io/update-center-mirror/)