Relay operators choose the time period they’ll keep your notes depending on their own preference. Some do not store info at all, but just re-broadcast notes. Some store notes for a month, and some act as “Nostr archives”. If you want to ensure that all of your notes are saved for eternity, you should run your own relay. Otherwise something like wss:/relay.nostr.band is well worth connecting to.
Discussion
I'm considering running my own eventually. Is there a server listing of how long it's kept for?
I'm looking for ones which don't keep them indefinitely.
I doubt it. You could figure this out if you’re technical enough and can assess the code, but this ain’t no trivial task.
It’s really outside of anyone’s control.
Anyone can repost your notes and they will spread to their relays too.
Anyone can get your notes from the relays you connect to and then store them under their own policies.
Your notes are public and once published they are extremely difficult to control by anyone, including you.
If you want ephemeral then nostr is not it.
Yah, I get the implications and that it depends on participants upholding the retention wishes.
But most of my posts won't be boosted and its good to let go of things. It I find the time I might write my own relay to experiment.