If you would like to move your certificate(s) into a bundle file, you can use a cat command in a Linux bash
example: cat domain_com.crt domain_com.ca-bundle.crt > ssl-bundle.crt
note: “domain_com.crt” is your End Entity certificate file
“domain_com.ca-bundle.crt” is your Root and Intermediate certificates bundled in this file.
In the event you have received the root and intermediate certificates separately, run the following command.
example: cat domain_com.crt USERTrustRSAAddTrustCA.crt AddTrustExternalCARoot.crt > domain_com.ca-bundle.crt
If you are using a GUI based Text Editor (such as; Notepad)
Here is how to concatenate the certificate files into single bundle file:
Open domainname.crt and domainname.ca-bundle files using any text editor.
Copy all the content of domainname.crt and paste it on the top of domainname.ca-bundle file.
Save the file name as ‘ssl-bundle.crt’.
To concatenate your certificate with your private key:
1. Generate CSR
openssl req -new -newkey rsa:2048 -nodes -keyout path:\server.key -out path:\server_csr.txt
2. Download the certificate with your chain from SCM (eg: my_certificate.cer)
3. Concatenate the certificates with your private key:
openssl pkcs12 -export -out path:\[new cert bundle name].pfx -inkey path:\server.key -in path:\my_certificate.cer
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