_Originally created by @sajolida on [#16535 (Redmine)](https://public-redmine-archive.tails.boum.org/code/issues/16535)_ # Inspiration and design Cf. how Fedora does it: - https://fedoraproject.org/wiki/Changes/DNF_Better_Counting - the initial "countme" idea by Lennart Poettering, that lead to the "DNF Better Counting" proposal, i.e. with no need for UUIDs: <https://lwn.net/ml/fedora-devel/20190108152239.GA24118@gardel-login/> - The high-level story: https://lwn.net/Articles/776327/ And another UUID-less design (that was not implemented): https://wiki.mozilla.org/MetricsDataPing#Anonymous_alternative For Tails, we could send a “countme” along with the fetch of the security update feed every time a persistence is mounted in a new month, based on the “Last mount time” of `/dev/mapper/TailsData_unlocked`. This would allow us to count the unique installations of Tails with persistence used in a given month (or week) in a privacy-preserving way. It would complete the picture that we already have on: - Boot counts - Downloads (tails/tails#14922) # Specs - Granularity per week - It's OK if this does not give us accurate with/without persistence ratio: we have data about the portion of Tails users with persistence elsewhere already (WhisperBack reports). # Combine this with reporting version number Combining this with reporting version number (#17545) would have the following advantages: - Single requests with both information - Only once per week if Persistent Storage - Every time if no Persistent Storage ⇒ we can't de-duplicate those boots from the same device. - Additional bit in the encrypted data - Single tooling to parse and extract data - The resulting data is more useful, e.g. gives us how many _installs_ are outdated, not how many _boots_ were done from an outdated Tails. # Next steps 1. [ ] draft design based on sysadmins' proposal for #17545 2. [ ] ask sysadmins to review the design and improve like the smart security/privacy-minded people they are, rinse and repeat 3. [ ] implement: Tails-client-side code [FT] + parsing code [sajolida] 4. [ ] deploy in Tails 5. [ ] iterate at will And optionally, figure out how maybe some day the data processing + output publication could be done automatically on our infra, instead of manually by 1 person who first has to get access to tons of logs.