Most actions federate, any exceptions which aren't federated yet are generally just there because the federation logic has not been implemented (but improvements are constantly being worked on).
Generally federating the modlog is mostly just there for informative purposes. As in, we can check what mod actions were taken on instance A through the modlog on instance B (and there is no mechanism in Lemmy for other instances to retroactively remove or hide federated modlog items, btw).
For the backend: our traffic is load balanced between multiple servers, so I can just spin up a new server with the latest version of Lemmy, add it to the load balancer, and then start taking down the servers with older versions. That way, there is no disruption at all for users, because there is always a server available to handle incoming traffic. The only requirement for this is that the new version of Lemmy can't have database migrations which break the old running servers.
For lemmy-ui: it's a bit more complicated, because even with a load balancer, it's still possible that one user making multiple sequential requests can end up getting responses from different servers. This is problematic, because during an upgrade, files from the new version are not available on the old servers, and vice versa. Fortunately, there are many ways to solve this problem, for lemm.ee, the solution I use is to just always serve lemmy-ui files from object storage, for all versions. In other words, after I upload lemmy-ui files for a new version, these will immediately also be available on old servers.
By the way, as a mini-present, I have sneakily updated our Lemmy to 0.19.4! It was possible to do this one without any downtime, so I just did it quietly in the background.
While there isn't any built-in ban appeal in Lemmy, there are still a few ways to reach lemm.ee admins even after a full ban: creating a new account (as you did), contacting me on Matrix (I am @sunaurus:matrix.org), or contacting the admins on Discord (there is an invite to the lemm.ee Discord in the sidebar of this community).
Well, one advantage we have over commercial social media is that they need to pay people to write code and maintain the infrastructure, but a lot of work on Lemmy is volunteer-based.
Many admins for bigger instances are basically on-call the whole year for free, open source contributors provide code for free, etc. Even the core maintainers are effectively losing money by working on Lemmy, because while they are getting some income, the sum of money they are getting from working on Lemmy is way smaller than what they would get if they worked typical software engineering jobs.
Basically, if any non-volunteer organization wanted to replicate Lemmy, it would cost them quite a bit more in terms of payroll alone.
Another aspect is scale - Lemmy is able to spread the costs between different instances, and while growth of the network can generally increase costs for individual nodes, they will still end up paying less compared to if they were hosting the entire social network in a centralized way.
We have about 3.3k monthly active users. This is based on users who at least vote/comment/post once a month, so it doesn't include lurkers. But yeah, in terms of just infrastructure costs, we're at about 6 cents per active user per month.
We've been stable just around 200€ per month for most of this year (it fluctuates up and down a little bit depending on exact usage). I update https://status.lemm.ee once every month with expected running costs for that month, and while it hasn't changed much in the past months, if it does ever change, you'll find up to date info there!
They are using an allowlist rather than a blocklist, unlike most big instances. We are linked, but we're not on their allowlist, so the result is still that they block all federation from lemm.ee.
Aha, I think this restore feature is missing from the standard Lemmy UI.
Maybe this will help: I quickly implemented a very basic restore button on lemmy-ui-next. Can you check if you see a "Restore" button in the sidebar at https://next.lemm.ee/c/eurographicnovels? Note that you must be logged in as a moderator to see this button.
I need to step away from my computer for a while, but if this doesn't work, then I will be able to look into it further during the weekend.
Purging is something that can't really be used to hide mod actions, as any federated instances will still retain their copy of any purged content. Purging is a feature which is only really useful for completely removing illegal content from our servers, it's used quite rarely and in fact leaves a trace in the mod log as well.
Our mod log will show all federated mod actions, not just actions by lemm.ee mods and admins. So if any other instance is generating a ton of actions, it will also be visible from our mod log. In fact I don't think there has been any increase recently in lemm.ee mod actions at all.
The mod log does not actually get cleared, there is simply a UI issue in Lemmy which makes it a bit hard to view the mod log chronologically. The UI makes it appear as if the mod log is one single list of actions, while in fact it's different lists combined together (one list per each action type). You will notice some really old actions even on the first page of the mod log, this makes it seem as if there is a "missing period" in the actions, while in fact you are actually just seeing the first page for each different action type. If you navigate to subsequent pages, you will find all the "missing" actions there.
In practical terms, it's not really possible to clear the mod log at all, thanks to federation. Even if one instance will delete their local mod log records, those records would still be visible in other instances which they previously federated out to.
I agree that using the mod log to attack other users with inaccurate mod action reasons is not really justifiable.
We now have some additional guidance about this here under the moderator responsibilities section:
Ensure that they only provide accurate and clear reasons for mod actions
I will make a separate announcement post about this as well shortly.
Unfortunately, due to the nature of mod log federation on Lemmy, it's not really possible to retroactively change mod action reasons currently. I am sorry about that. If this does end up causing problems for you in the future, you could point people to this thread for context.
Banning a local user from a local community does actually federate already