How to create a self-signed or trusted third-party certificate with openssl

This document (7023144) is provided subject to the disclaimer at the end of this document.

Environment

SUSE Linux Enterprise Server 11

Situation

Resolution

How to generate a self-signed or trusted third-party certificate using openssl:

Generate a Private Key by following the steps below from a terminal window:
- openssl genrsa -des3 -out server.key 2048
- Type the pass phrase to protect the key and press [Enter]
- Re-enter the pass phrase.
Generate a Certificate Signing Request by following the steps below:
- openssl req -new -key server.key -out server.csr
- Enter the pass phrase of the private key created in Step 1.
- Fill in the Country Name, State or Province Name, Locality Name, Organization Name, Organizational Unit Name, Common Name, Email Address.
  Note: The Common Name should be the DNS name of the server (i.e. server.mydomain.com).
- When asked for a Challenge password and optional company name, leave it blank.
To sign the certificate, please select from the following options:
- (Trusted 3rd-party Certificate Authority) Send the Certificate-Signing Request (CSR) to the third party for their signing. The following files should be received:
  - Server certificate (public key)
  - Intermediate CA and/or bundles that chain to the Trusted Root CA
- (Self-signed) Sign the certificate with openssl:
  - openssl x509 -req -days 730 -in server.csr -signkey server.key -out server.crt
    Note: Increase or decrease 730 as needed. This is the number of days the certificate is valid for.
  - Enter the pass phrase of the Private Key. This is the same pass phrase that was entered in Step 1.
(optional) If needed, create a concatenated PEM file:
TID 7013103 - How to create a .pem File for SSL Certificate Installations

Additional Information

TID 7015502 - Common Mistakes in SSL Certificate Management & Implementation.

TID 7013103 - How to create a .pem File for SSL Certificate Installations.

Disclaimer

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