Issue Phusion Passenger on CentOS 8 causes nginx and apache stop commands to hang until timeout

[websavers]

This is a weird one. The commands systemctl stop httpd and systemctl stop nginx hang until timeout (90s) on CentOS 8.

I narrowed it down to Phusion Passenger -- once removed (via Plesk Installer), nginx and httpd stop normally. When I reinstall Passenger (which I kinda need for nodejs and ruby support), the issue returns.

When I check nginx and apache logs, Phusion Passenger reports as stopping within seconds of the stop command, but for some reason systemctl doesn't seem to realize it. The logs don't indicate any actual problems with Phusion Passenger.

passenger-6.0.6-2.centos.8+p18.0.31.0+t201020.1804.x86_6
CentOS Linux release 8.2.2004 (Core)
Plesk Obsidian Version 18.0.31

 

[websavers]

For unknown reasons this doesn't appear to be a problem with apache restarts anymore. I reinstalled Phusion and the apache service appears to be able to stop fine. However nginx is still an issue. If I edit /usr/share/passenger/phusion_passenger/locations.ini and comment out nginx_module_source_dir=/usr/share/passenger/ngx_http_passenger_module nginx then restarts fine again without the 1.5 minute delay.

From what I can tell Plesk integrates with Phusion through apache such that requests are proxied with nginx like this:

Incoming request -> nginx -> apache -> phusion

If this is accurate, then the changes I made above should be fine. Does anyone know if any of the Phusion services are launched direct through nginx like the following?

Incoming request -> nginx -> phusion

As I'm assuming that the changes I made will break that, if so.