Command Line CSR Generator for Keytool
Common name - Must match the exact URL you plan to secure – is usually your fully-qualified domain name (e.g. devel.ssl247.co.uk or mail.devel.ssl247.co.uk). Remember the www. is important – include it if you want to secure https://www.yoursite.com.
Organisation - The legal (officially registered) name of your organisation, it includes Inc, LLP, Pvt, Plc, Ltd, SARL, etc.
Organisational unit - The name of your department within the organisation (this is often "IT," "Web," or is just left blank).
City/locality - The city or town in which your organisation is located.
State/province - The state in which your organisation is located.