What are the Salesforce IP Addresses & Domains to whitelist?
Knowledge Base - FAQ
What are the Salesforce IP Addresses & Domains to whitelist?
If you need a range of IP addresses for Salesforce so that the customer can whitelist, it needs to come from Salesforce. You can refer to this Salesforce Knowledge Article that maybe usefull: 3652 - What are the Salesforce IP Addresses & Domains to whitelist?