https://sectigo.com/resource-library/install-certificates-nginx-webserver
https://support.sectigo.com/Com_KnowledgeDetailPage?Id=kA01N000000zFKz
(How do I make my own bundle file from CRT files?)
https://support.sectigo.com/Com_KnowledgeDetailPage?Id=kA03l00000117LT
(Certificate Chain Diagram)
1. Refer to the above link to create the ca-bundle.crt
#cat SectigoRSAOrganizationValidationSecureServerCA.crt USERTrustRSACertificationAuthority.crt USERTrustRSAAAACertificateServerice.crt > domain.ca-bundle
2. Create the server.crt
#cat STAR_domain.crt domain.ca-bundle > server.crt
3. Prepare the server.key
#cp wildcard.domain.key server.key
4. Replace /etc/nginx/ssl/server.crt and server.key by the above two file
5. Restart the nginx server
#systemctl restart nginx
Verify the certificate expiration date.
server.crt format
1. domain cert
2. rsa cert
3. root cert
4. cross-sign cert
