SSL

#Generate CSR

# shell
openssl req -nodes -newkey rsa:2048 -keyout server.key -out server.csr

Source: https://support.comodo.com/index.php?/Knowledgebase/Article/View/1/19/csr-generation-using-openssl-apache-wmod_ssl-nginx-os-x

#Sample

$ openssl req -nodes -newkey rsa:2048 -keyout server.key -out server.csr
Generating a 2048 bit RSA private key
writing new private key to 'server.key'
-----
You are about to be asked to enter information that will be incorporated
into your certificate request.
What you are about to enter is what is called a Distinguished Name or a DN.
There are quite a few fields but you can leave some blank
For some fields there will be a default value,
If you enter '.', the field will be left blank.
-----
Country Name (2 letter code) [AU]:
State or Province Name (full name) [Some-State]:VIC
Locality Name (eg, city) []:Melbourne
Organization Name (eg, company) [Internet Widgits Pty Ltd]:linkedlist.org
Organizational Unit Name (eg, section) []:
Common Name (e.g. server FQDN or YOUR name) []:linkedlist.org
Email Address []:

Please enter the following 'extra' attributes
to be sent with your certificate request
A challenge password []:

#Create Bundle from Issued Certificate

# shell
cat server.crt COMODORSADomainValidationSecureServerCA.crt COMODORSAAddTrustCA.crt AddTrustExternalCARoot.crt > server-ssl-bundle.crt
# or
cat server.crt server.ca-bundle > server-bundle.crt