...
To add a Salesforce license server to License Statistics, you'll need to provide a Salesforce security tokenSecurity Token, as described in Obtaining Salesforce credentials, below.
...
You’ll need to fill out the following required fields when adding your Salesforce license server: Login, Token and Password. While login and password are credentials you use to access your Salesforce account, your security token Security Token is automatically sent to you via email when you set up a Salesforce account, when your salesforce.com password is changed or when you request to reset your security tokenSecurity Token. (For more information about security tokensSecurity Tokens, please refer to this Salesforce knowledge article.)
Once you have the token, you can add your Salesforce license server using the Realtime License Servers tab in the Administration page, as detailed in Adding and editing license servers.