Is there anything special about user 'shiny' that would stop it logging in to RStudio Server?

I've installed RStudio Server and Shiny Server on an Amazon linux (CentOS) instance in AWS and everything works well, including accessing through reverse proxy, etc. To troubleshoot a Shiny app I wanted to log in to RStudio Server as user "shiny" (to test if it can access a particular database) and find that I get "Incorrect or invalid username / password". I have no problem doing switching to user shiny in a shell by su shiny and shiny's password.

So far, I have tried changing shiny's password, stopping, starting and re-starting RStudio Server, checking there's no group specified in the rstudio.conf file (no, it's empty, as per out of the box), checking shiny's user id is > 100 (it is 996, see below). I haven't completely run out of things to check yet but was wondering, is there anything special about user shiny that would stop it logging in to RStudio Server?

Here's the user ids. ellisp is a user who can log on to RStudio Server; shiny is a user that can't.

$ id ellisp
uid=1001(ellisp) gid=1002(ellisp) groups=1002(ellisp),10(wheel)
$ id shiny
uid=996(shiny) gid=1001(shiny) groups=1001(shiny)

Does the shiny user have a home directory and local system account? If not, RStudio Server won't be able to launch an R session for them (see here:

Yes, and I can use su shiny in a shell to switch to shiny and start up R in the shell (in fact this was good enough for all my troubleshooting, but it would still be nice to know how to use RStudio in the future).

Hmm, the only other thing I can think of is that there's some issue with PAM. You may want to try PAMtester ( and see if there any specific errors being reported between that particular account and your PAM setup.


You need to just change the configuration of RStudio Server. By default it won't allow logins from UIDs below 1000. Change the auth-minimum-user-id setting in the RStudio Server configuration. I dropped it to 950 and it worked perfectly.


1 Like