Generate the Certificate Signing Request (CSR)

Use OpenSSL. In this example, the client private key is saved in a file named client.key, and the CSR is saved in a file named client.csr:

$ openssl req -newkey rsa:2048 -nodes -keyout client.key -out client.csr
Generating a 2048 bit RSA private key
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writing new private key to 'client.key'
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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.
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Country Name (2 letter code) [XX]:US
State or Province Name (full name) []:California
Locality Name (eg, city) [Default City]:Santa Clara
Organization Name (eg, company) [Default Company Ltd]:HPE
Organizational Unit Name (eg, section) []:MapR
Common Name (eg, your name or your server's hostname) []:maprkmipclient1
Email Address []:security@hpe.com

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