Serve a file to download - doesn't work after mup deploy to server

i have one file to share to users, so i just

<a href="/">DOWNLOAD</a> 

; tested fine on local meteor app at my home ubuntu16; i’m able to click and download the file.
when i pull the code from git on the office ubuntu16 computer (which mup is installed, and the is there too), after mup deploy, it doesn’t work on the real server. i guess the file has not been upload to server by mup? what should i do? use nginx to build another website for downloading?
any suggestions? thank you!