Given that I asked the question in the first place, here is how I make sense of it after some answers and looking at the modlog.
What I don’t understand is why does server B have to tell server A that user@B is banned on B, instead of just not letting user@B login anymore and thus disallowing the creation of further content by user@B?
Because A sees B's content, but on A server. user@B is banned on B, hence, A keeps seeing B content, but not user@B content on B. user@B can still register on A and post there.
And maybe A wants the content by user@B, so why can server B dictate bans that server A has to enforce?
Because user@B's content, while copied and displayed on A, is still B's content. B bans the user and their content everywhere. Again, user@B can register elsewhere and start posting.
What happens if server A ignores them?
From what I can see, if I am A, I cannot unban user@B in any way. user@B can register in my instance, though. I can ban user@A afterwards (or not).
As an instance would I be able to flood another instance’s ban list by just pretending to have trillions of users that are all banned?
I think so. I federate with Beehaw. If Beehaw bans everyone, my banned user list will get quite long.
If I am server A, and I federate with B. If user@B is banned by B, this is propagated to me, so that A does not see content from B that comes from user@B. It makes sense.
Amministro la mia istanza. Non vedo indirizzi IP di utenti.
Tieni conto però che se amministri anche il server, puoi accedere ai log del server Web che serve Lemmy. Quello può contenere gli indirizzi IP di tutte le richieste e con un po’ di lavoro puoi arrivare a correlare un indirizzo IP a un utente.
Usa una VPN commerciale che usano potenzialmente in tanti se ci tieni a nascondere il tuo IP fisso. Il tuo sarebbe tra l’altro uno dei pochi usi davvero utili di una VPN.
Given that I asked the question in the first place, here is how I make sense of it after some answers and looking at the modlog.
Because A sees B's content, but on A server. user@B is banned on B, hence, A keeps seeing B content, but not user@B content on B. user@B can still register on A and post there.
Because user@B's content, while copied and displayed on A, is still B's content. B bans the user and their content everywhere. Again, user@B can register elsewhere and start posting.
From what I can see, if I am A, I cannot unban user@B in any way. user@B can register in my instance, though. I can ban user@A afterwards (or not).
I think so. I federate with Beehaw. If Beehaw bans everyone, my banned user list will get quite long.
Everything is running fine. It is as @jon@jon@lemmy.tf and @neoney@lemmy.neoney.dev write.
If I am server A, and I federate with B. If user@B is banned by B, this is propagated to me, so that A does not see content from B that comes from user@B. It makes sense.
Thank you, it appears to be this way.
Yes, they all are only from instances I federate with.
I can’t test it but it seems that I cannot unban them from my instance. Meaning that a ban is at federation level.
Yes. I have a VPS and I am using their Docker files: https://join-lemmy.org/docs/en/administration/install_docker.html
Non ho mai aperto il database di Lemmy. Se lì viene registrato l’indirizzo IP dell’utente, è ancora più semplice, vero.
Amministro la mia istanza. Non vedo indirizzi IP di utenti.
Tieni conto però che se amministri anche il server, puoi accedere ai log del server Web che serve Lemmy. Quello può contenere gli indirizzi IP di tutte le richieste e con un po’ di lavoro puoi arrivare a correlare un indirizzo IP a un utente.
Usa una VPN commerciale che usano potenzialmente in tanti se ci tieni a nascondere il tuo IP fisso. Il tuo sarebbe tra l’altro uno dei pochi usi davvero utili di una VPN.