Comment on What happens to the content if an Lemmy instance shuts down?
Xylight@lemdro.id 3 days ago
The way ActivityPub federation works, once an instance is “linked” (like lemm.ee linking with lemmy.world, lemdro.id, etc), the instance will now send them an event once a post is made or something like that.
For example:
- lemm.ee —links–> lemmy.world
- lemm.ee user makes a post A
- lemm.ee —notifies–> lemmy.world
- lemmy.world makes a copy of post A.
So yes, every Lemmy instance stores copies of new data from other instances once they link.
TrivialKin@lemm.ee 3 days ago
What about the old data? Are they also stored retroactively once the link happens?
And about the linking, from what I gather, (taking your example) as long as any one user from
lemmy.worldfrom retrieves posts fromlemm.ee, or if they subscribe to it, the “link” will happen. Is that correct?Is there anyway to verify that the data is persisted on
lemmy.world? As long as the post/community is visible right now fromlemmy.world, would it be indication that it will be there even afterlemm.eeshuts down?sevon@lemmy.kde.social 3 days ago
When instances federate, they don’t send old content. Old content will be fetched if a user tries to open it, for example by clicking a link to an old post (on some apps) or pasting its url into the search box.
The data copied to the other instance will stay on the other instance, unless manually deleted for some reason.
Rentlar@lemmy.ca 3 days ago
So if a brand new instance is started, it does not retroactively receive any content from other servers. Only ones that were connected by a link at the time content was posted will have a copy, essentially.
To know which posts will be kept on different servers, look up your own username, e.g. lemmy.ca/u/TrivialKin@lemm.ee