My home instance is shutting down soon.

https://lemm.ee/post/65824884.

I am slightly unclear about what the instance admin meant.

Because of how Lemmy is built, everything posted on lemm.ee will still be accessible from other instances, even after we go offline.

How are other Lemmy instance able to access the content from the post-shutdown lemm.ee?

Do all the other Lemmy instances keep a copy of the content from lemm.ee?

If so, wouldn’t that be rather taxing on each Lemmy instance? (since they have to keep a copy of all the content from all instances they federate with).

I tried reading this up by researching on Lemmy federation, but this is still unclear to me.

    • Skull giver@popplesburger.hilciferous.nlEnglish
      0·
      13 hours ago

      I don’t see why not. Based on the spec, a server submits a request signed by a keyId which the receiving server caches or obtains, but the new server is also queried for the keys belonging to the actor. You cannot reuse the old key IDs (probably) because it’ll stay in the cache, but you can just add new keys of your own.

      Step 10 of the key verification algorithm explicitly instruct the server to ignore the old key and fetch a new one, in case the other server has done a blind key rotation.

      In other words, the ActivityPub spec only verifies that an account was the source of a message at the time a server submitted or forwarded an event. It does not validate that an Update with new text contents belongs to the same server that once Created the object.

      Of course, I expect ActivitiyPub software to (mis)implement this spec in different ways. Some software will be protected against domain hijacking, others will leave domains once registered completely useless in the future for common actor names in ActivityPub.