shiny-server timeout nginx

error in nginx:

upstream prematurely closed connection while reading response header from upstream



In the shiny-server configuration help, there are two timeouts that can be set in the free shiny server version.

app_init_timeout — Describes the amount of time (in seconds) to wait for an application to start. After this many seconds if the R process still has not become responsive, it will be deemed an unsuccessful startup and the connection will be closed.

app_idle_timeout — Defines the amount of time (in seconds) an R process with no active connections should remain open. After the last connection disconnects from an R process, this timer will start and, after the specified number of seconds, if no new connections have been created, the R process will be killed.

It could be that the javascript error is thrown, because the R process was killed.  You can edit the configuration file to increase the time-out periods, adding:

# Instruct Shiny Server to run applications as the user "shiny"

run_as shiny;

# Define a server that listens on port 3838

server {

listen 3838;

# Define a location at the base URL

location / {

# Host the directory of Shiny Apps stored in this directory
site_dir /var/shiny-server/www;
# 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 off;
app_init_timeout 250;



This brings us right to the next question,…

Where do I find my shiny server configuration file?

There is a hard coded configuration file, but in the search path there is one located in:


here you can do the above edits. After you have  done the edits you want to reload the configuration…

How do I reload the Configuration File, how to start or stop the shiny server?

#reload without restarting
sudo reload shiny-server
#stop the shiny server 
sudo stop shiny-server
#start it...
sudo stop shiny-server