当在服务器上执行修改时，Ruby/Rails显示通用屏幕。

I have a ruby on rails app running a server and sometimes it needs to be taken down for updates/etc. As of now, one way I see to have a general display screen during update periods (when the app is down) is to substitute the files within /srv/www/ directory to just have it display a general screen everywhere that the user could possibly navigate to. I also thought of having a central controller file that connects all others (essentially a main) but this seems counter intuitive for rails.I have a ruby on rails app running a server and