Performing bulk actions on "flags" causes nginx 503 error

[Future]

Hello,

Whenever I attempt to use a bulk action on all the flags displayed under the /flags webpage it triggers a 503 error like below.
What's strange is that it seems the bulk actions are applied "randomly" to some flags while others remain unprocessed. What could I do to debug this?
As anyone else reported anything similar?

I'm using the following software

NodeBB version
v3.3.6

NodeBB git hash
7fb3879

NodeJS version
v18.16.0

Installed NodeBB plugins
[email protected] (installed, enabled)
[email protected] (installed, enabled)
[email protected] (installed, enabled)
[email protected] (installed, enabled)
[email protected] (installed, enabled)
[email protected] (installed, enabled)
[email protected] (installed, enabled)
[email protected] (installed, disabled)
[email protected] (installed, disabled)
[email protected] (installed, disabled)
[email protected] (installed, enabled)
[email protected] (installed, enabled)
[email protected] (installed, disabled)
[email protected] (installed, disabled)
[email protected] (installed, disabled)
[email protected] (installed, enabled)

Database type
MongoDB

Database version
v6.0.4

[Future]

Hello again, I guess it's a classic when someone asks an issue and then they figure out something later.
It was my nginx config

[baris]

@Future you should post what you did to fix it so others who run into the same issue can benefit.

[julian]

This likely cropped up because flag actions now use the v3 API instead of socket.io, so it could be it overloaded the backend, which started sending 503s.