this post was submitted on 22 Aug 2025
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"Antiyanks" is back at it again and has switched tactics to spamming a massive number of comments in a short period of time. In addition to being annoying (and sad and pathetic), it's having a deleterious effect on performance and drowns out any discussions happening in those posts. That spam also federates as well as the eventual removals, so it's not limited to just the posts being targeted.

Looking at the site config for the home instance of the latest ~~two~~ three alts, the rate limits were all 99999999. ๐Ÿคฆโ€โ™‚๏ธ

Rate limits are a bit confusing, but they mean: X number of requests per Y seconds per IP address.

The comment API endpoint has its own, dedicated bucket. I don't recall the defaults, but they're probably higher than you need unless you're catering to VPN users who would share an IP.

Assuming your server config is correctly passing the client IP via the XFF header, 20 calls to the /create_comment endpoint per minute (60 seconds) per client IP should be sufficient for most cases, though feel free to adjust to your specific requirements.

Edit: A couple of instances accidentally set the "Messages" bucket too low. That bucket is a bit of a catch-all for API endpoints that don't fit a more specific bucket. You'll want to leave that one relatively high compared to the rest. It's named "Messages" but it covers far more than just DMs.

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[โ€“] Sal@mander.xyz 3 points 10 hours ago (1 children)

Thanks!

I was able to crash the instance for a few minutes, but I think I have a better idea of where the problem is. Ths $emote_addr variable seems to work just the same.

In the rate limit options there is a limit for ''Message''. Common sense tells me that this means 'direct message', but setting this to a low number is quite bad. While testing I eventually set it to '1 per minute' and the instance became unresponsive until I modified the settings in the database manually. If I give a high number to this setting then I can adjust the other settings without problem.

[โ€“] admiralpatrick@lemmy.world 3 points 10 hours ago (1 children)

"Message" bucket is kind of a general purpose bucket that covers a lot of different endpoints. I had to ask the lemmy devs what they were back when I was adding a config section in Tesseract for the rate limits.

These may be a little out of date, but I believe they're still largely correct:

[โ€“] Sal@mander.xyz 3 points 10 hours ago (2 children)

So, ultimately my problem was that I was trying to set all of the limits to what I thought were "reasonable" values simultaneously, and misunderstood what 'Message' meant, and so I ended up breaking things with my changes without the reason being obvious to me. I looked into the source code and I can see now that indeed 'Messages' refer to API calls and not direct messages, and that there is no 'Direct Message' rate limit.

If I let 'Messages' stay high I can adjust the other values to reasonable values and everything works fine.

Thanks a lot for your help!! I am surprised and happy it actually worked out and I understand a little more ๐Ÿ˜

[โ€“] BlueEther@lemmy.nz 2 points 8 hours ago (1 children)

Hi I think I set the messages too low as well and now no.lastname.nz is down, pointers on how to fix with no frontend?

[โ€“] admiralpatrick@lemmy.world 3 points 8 hours ago* (last edited 8 hours ago) (1 children)

If you have DB access, the values are in the local_site_rate_limit table. You'll probably have to restart Lemmy's API container to pick up any changes if you edit the values in the DB.

100 per second is what I had in my configuration, but you may bump that up to 250 or more if your instance is larger.

[โ€“] BlueEther@lemmy.nz 3 points 8 hours ago

local_site_rate_limit

Thanks: UPDATE local_site_rate_limit SET message = 999, message_per_second = 999 WHERE local_site_id = 1;

[โ€“] admiralpatrick@lemmy.world 2 points 9 hours ago (1 children)
[โ€“] Sal@mander.xyz 2 points 9 hours ago

๐Ÿ˜ ๐Ÿ‘