My main account is dark_arc@social.packetloss.gg. However, as of roughly ~~24-hours ago~~ (it seems this has been going on since March 10th and gotten worse since) it seems like the server has stopped properly retrieving content from lemmy.world.
It's been running smoothly for well over 9 months, and (I think) working fine for content coming in from other instances. So I'm curious if anyone else experienced anything strange with lemmy.world federation recently?
Setup Description
The server flow in my case is as follows:
[Public Internet] <-> [Digital Ocean Droplet] <-> [ZeroTier] <-> [Physical Machine in my Basement (HW Info)]
The Digital Ocean droplet is a virtual host machine that forwards requests via nginx to the physical machine where a second nginx server (running the standard lemmy nginx config) then forwards the request to the lemmy server software itself.
Current Status
Lemmy Internal Error
I've found this is my lemmy logs:
2024-03-24T00:42:10.062274Z WARN lemmy_utils: error in spawn: Unknown: Request limit was reached during fetch
0: lemmy_apub::objects::community::from_json
at crates/apub/src/objects/community.rs:126
1: lemmy_apub::fetcher::user_or_community::from_json
at crates/apub/src/fetcher/user_or_community.rs:87
2: lemmy_server::root_span_builder::HTTP request
with http.method=POST http.scheme="http" http.host=social.packetloss.gg http.target=/inbox otel.kind="server" request_id=688ad030-f892-4925-9ce9-fc4f3070a967
at src/root_span_builder.rs:16
I'm thinking this could be the cause ... though I'm not sure how to raise the limit (it seems to be hard coded). I opened an issue with the Lemmy devs but I've since closed it while gathering more information/making sure this is truly an issue with the Lemmy server software.
Nginx 408 and 499s
I'm seeing the digital ocean nginx server reporting 499 on various "/inbox" route requests and I'm seeing the nginx running on the physical machine that talks directly to lemmy reporting 408 on various "/inbox" route requests.
There are some examples in this comment: https://lemmy.world/comment/8728858
Checking lemmy.world federation status at: https://phiresky.github.io/lemmy-federation-state/site?domain=lemmy.world . There, you can see that social.packetloss.gg is listed among the "407 failing instances".
You'll need to check if your server actually configured to receive federation traffics. If you're using cloudflare or some other web application firewall, make sure they're not doing any anti bots measures on the
/inboxendpoint. For example, in Cloudflare, create a new WAF rule (Security -> WAF) for/inboxand set it to skip all security.If you don't use any web application firewall at all, did you just upgraded your instance from v18.x to v19.x recently right before experiencing federation issue? v19.x has increased resource consumption and will have problem running on small server after running for a while. For small VPS (~4GB of RAM), you might want to adjust database pool_size to <30 on
lemmy.hjsonfile. Restarting lemmy AND postgres every once in a while also helps if you're on a small VPS.It's been up on 19.x for a few months now. It's also a full on bare metal server with a ton of resources, it's not at all starved.
It's almost like someone posted something to somewhere that "jammed" Lemmy and it just won't get past it but I'm not sure how to figure out what that would be or how to unjam things.
Could be postgres-related. Federation is only "jammed" if the source instance thinks your instance is having an issue because it takes too long to respond. Maybe enabling slow query log on postgres and then reviewing that log could point you in the right direction.