Neither of my posts from yesterday and today have made it out to their communities' home instance (lemmy.world), and neither has received any comments or votes. It seems like something to do with outgoing federation is stuck.
Edit to clarify:
The problem I'm seeing affects posts. I don't know if it affects comments.
It's possible that it only affects lemmy.world communities, but it definitely affects them even on other instances. Neither of these posts are showing up on any remote instance that I've seen:
https://lemmy.sdf.org/post/21620419
https://lemmy.sdf.org/post/21673588
6 days later, it's happening again:
https://lemmy.sdf.org/post/21974478
From my experience, lemmy.word can take hours to federate to no matter the instance. I think they might be using some weird shit for "last mile".
Hours wouldn't raise my attention. I'm talking days.
Given that lemmy.world uses Cloudflare, I wonder if their server is overloaded enough to sometimes exceed Cloudflare's 100 second timeout, triggering http-524 errors during federation.
From experience sh.itjust.works sometimes has this problem as well.
They also have one thing in common: Cloudflare
Perhaps it's getting "protected" from federation considered a DoS.
Would a federation problem on lemmy.world block propagation to slrpnk.net? That would be a weirdly inefficient network design.
That's (an example of) what I'm seeing right now. It's abnormal.
Can't wait to see what happens when/if they move to sublinks. How much worse can they get
I think kbin.social showed us that overload can get much worse.