We had this 503 error after each login on our older 3.x instance. After a refresh of the page, the session then works fine.

Now we have installed a plain vanilla 4.6.3 and migrated the mongodb.

Surprisingly the 503 issue is happening as well on the new instance.

Setup is with nginx and 3 NodeBB processes on same VM, and Redis cluster

I assume for some weird reason, the nodebb rate limiting kicks in, but strange that this only occurs after each new login, and reproducible.

Any suggestions how to diagnose or how to modify the rate limiting check to be less aggressive (or to exclude logins)?

Thanks Stefan

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[–] [S] 1 point 8 months ago

We did not modify the bcrypt_rounds parameter. You mean the password hashing in bcrypt could drive a cpu% spike which the traffic management erroneously interprets as too high load?

Does that really sound realistic that the CPU is that busy with a single login and the following hardware - one VM for nodeBB and the same for mongoDB Debian GNU/Linux 13 (trixie), Kernel 6.12.57 4 Cores x86_64 Architektur 8 GB RAM

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