When a Mastodon server is deleted, the network does not automatically recognize that you deleted the server. For remote servers, the domain associated with your Mastodon instance will simply stop responding. This is exactly the same as when the server is just temporarily offline.
This outcome may be desirable if you have a backup and plan to restore the server in the future. It may also be preferable if you want the posts, replies, and interactions from your server's users to persist on remote servers.
Additionally, it's important to understand that if a Mastodon server is just deleted, the domain or subdomain you used for your Mastodon installation should not be reused for a new Mastodon instance or the installation of any other ActivityPub-compatible software. Reusing the same domain/subdomain can cause federation issues with remote servers that still have cached data from the previous instance.
You can avoid this by running the Mastodon self-destruct command before shutting down your instance. But this will also request remote servers to delete all posts, interactions and accounts from their cache and those will be lost for remote users that might have favorited, boosted or that might expect access to your users profile data in the future.
Note that running the Mastodon self-destruct command does not guarantee that your server data will be deleted on remote servers but it’s requested to remote servers to do so and most will. Still, there might be some situations where that might not happen, be it for incompatibility of the ActivityPub software used or for other reasons.
Summary
If you JUST delete the server:
- You can restore it later if you have a full backup (including the remote media cache, for seamless restoration).
- Posts, replies, interactions and profile information from local users can continue to exist on remote servers.
- The domain or subdomain cannot be safely reused for a fresh Mastodon installation or other ActivityPub-compatible software.
If you run `self-destruct before deletion:
- Remote servers will be requested to delete all user data and content associated with your instance.
- The domain or subdomain can potentially be reused for a new Mastodon installation or other ActivityPub-compatible software (though this may not always work perfectly, as some ActivityPub implementations might not fully honor self-destruct requests).
When using Masto.host, if you want to run the self-destruct command you need to email info@masto.host to request it before your server is suspended/cancelled.