service account credentials with a shiny app hosted in a directory

In case it's relevant I found a reference to ensuring the preserve_logs is set to true in shiny server config. I did that and here's what it now looks like:

# Define a server that listens on port 3838
server {
  listen 3838;

  preserve_logs true;

  # Define a location at the base URL
  location / {

    # Host the directory of Shiny Apps stored in this directory
    site_dir /srv/shiny-server;

    # Log all Shiny output to files in this directory
    log_dir /var/log/shiny-server;

    # When a user visits the base URL rather than a particular application,
    # an index of the applications available in this directory will be shown.
    directory_index on;
  }
}

Then the person suggesting this says:

After restart of Shiny Server, access your application again, and check the log file. Usually there are useful information in the log file that could help you debug the issue.

However, I was unable to restart shiny because of this, where I am unable to run the restart command.

Not sure if the above is relevant or not, but preserve_logs did not exist in my config till I added it.