This hinges on two misunderstandings:

- That data processing always requires consent. There are exactly six reasons for storing or processing data: consent, contract fulfillment, legal compliance, vital interests of a natural person, public interest/official authority, or legitimate interest. Collecting IP addresses can be a legitimate interest, but:

- The real interesting question is what you do with the IP addresses after they're stored in a file. Securing your server is a legitimate interest. Tracking your users is generally not. Having lawfully collected data is not a carte blanche to do anything you choose with it.