To generate a self signed certificate in PEM format:
openssl req -new -x509 -newkey rsa:1024 -out selfcert.pem -days 1095
This creates a self-signed certificate (selfcert.pem) that will be valid for 1095 days (about three years) andalso generates a new private key to be output into a file named privkey.pem. If you already have a private key, use - key filename instead of -newkey rsa:1024 to specify the file containing the private key.
After generating the private key, the following prompts are displayed (example responses shown):
Enter PEM pass phrase: <password>
Verifying - Enter PEM pass phrase: <password>
Country Name (2 letter code) [AU]:US
State or Province Name (full name) [Some-State]:New York
Locality Name (eg, city) []:Millerton
Organization Name (eg, company) [Internet Widgits Pty Ltd]:CPS Inc.
Organizational Unit Name (eg, section) []:Engineering Common Name (eg, YOUR name) []:myclient.example.com
Email Address []:admin@example.com
Depending on the tool you use to create the certificate, you may also be asked for a challenge password and other optional information. Make sure you remember the password (and, if prompted, the challenge password) you specify, as you will need it to install the certificate.
The Common Name provided must be the DNS-resolvable fully qualified domain name (FQDN) used by the cluster. For a server certificate, when the client receives the certificate from the server, the browser will display a warning if the Common Name does not match the hostname of the request URI. For a client certificate, the Common Name in the client’s copy of the certificate is only compared to the Common Name in the copy on the server, so this can be any value.
cat selfcert.pem privkey.pem > clustercert.pem
clustercert.pem, on FortiADC and your clients, as appropriate.