Data Entry Trigger

To send REDCap data entry trigger to a server, you should relax SELinux policy first. Then you can set up your server through Nginx proxy or directly. Nginx proxy is the secure and recommended way. Direct way is non-secure and should be used for debugging purposes only.

Relax SELinux policy

setsebool httpd_can_network_connect 1

To retain the above modification after reboot, you can define a cron job:

# switch to root user
sudo su -

# install the new cron job
crontab -e

# you are in a visual editor now
# insert the following at the end of the file, save, and exit
@ reboot setsebool httpd_can_network_connect 1

---

Before setting up your server in either way, make sure lochness is listening to port 9999.

Through Nginx proxy

• Install nginx:

yum install nginx

• Enable it to auto-start upon reboot:

systemctl enable nginx

• location block in nginx.conf:

    server {
        
        ...

        location /redcap {
                proxy_pass http://localhost:9999/;
        }

        ...

    }

• service nginx restart

• Test data entry trigger from within REDCap using the URL http://my.server.com/redcap^~

Directly

• Open port 9999 through firewall:

firewall-cmd --permanent --add-port=9999/tcp

• Test data entry trigger from within REDCap using the URL http://my.server.com:9999^~

---

^~ You are welcome to use https protocol if Nginx is configured accordingly.