nginx 502 Bad Gateway

[Len]

I started getting nginx 502 Bad Gateway error recently. When I reboot it will work for few minutes and then error out again. Nothing shows in fs_cli besides that it happens when its reaching 50 - 60 registrations. Where can I look for logs etc ?

 

[DigitalDaz]

Have a look in:

/var/log/nginx/error.log

50-60 isn't allot unless you are running a very under resourced VPS.

 

[Len]

Have a look in:

/var/log/nginx/error.log

50-60 isn't allot unless you are running a very under resourced VPS.

Thx DD.
For readers who might be experiencing same. Ended up being a fail2ban issue. Specifically, a script running from a different machine was causing upstream error due to fail2ban. This can mean an easy attack on GUI of any fusionpbx server.

 

[DigitalDaz]

Can you explain this more please?

 

[Len]

Here is an example. I can run https://yourdomain/app/fax/anyscript.php from any computer. If I run it via curl in cron (not from https://yourdomain) every minute fail2ban will somehow hang Nginx with 502.