参考https://*.com/questions/41975528/make-all-gerrit-repositories-read-only

在特定时候需要把gerrit设置为只读模式，比如备份gerrit数据，可以用如下方法

Just set "ALLOW Read" in "refs/*" reference for "Anonymous Users" group (all users signed in or not) or "Registered Users" group (all signed in users) at the "All Projects" project and set "Rights Inherit From" to "All Projects" for all repositories in Gerrit.

To change project permissions go to: Projects > List > Select-the-project > Access

把All project 中的refs/* 设置为ALLOW Read, push ， write 相关的权限全部关闭即可