How to use a Certificate Chain on an Opengear?

Create the ssl_cert.pem text file. The certificates for the cert chain will all need to be in PEM format, and listed as follows: server cert, intermediate cert(s) and finally the root ca cert.

openssl or https://www.sslshopper.com/ssl-converter.html can be used to change certificate formats from crt/der binary to pem format.

Create the ssl_key.pem text file. This is the private key for the wildcard certificate.

SCP using SecureFX or WinSCP these certs to Opengear /etc/config/ directory. Connecting as the root user.

/etc/config/ssl_key.pem
/etc/config/ssl_cert.pem

SSH into the Opengear as root and run the command below

dos2unix /etc/config/ssl_key.pem
dos2unix /etc/config/ssl_cert.pem
config -a

If the browser is still showing the old certs, try and reboot the Opengear device.