Issue 502 Error

[Vakarian]

Hello,

whenever I or another customer changes something in the Plesk interface (adding/deleting subdomains etc...) all websites (also from other customers) on the same server get a 502 error from ngnix.

Is there anything you can do about it?

Yours with best regards,
Vakarian

 

[Ales]

Plesk needs to restart the web server after related changes, so that they take effect. During the restart, visitors can indeed encounter a short 502 error.

There are two things you can do:

a) prevent Plesk from restarting the Apache web server too often, this can be done under Tools & Settings -> General Settings -> Apache Web Server Settings

Choose a longer Apache restart period, perhaps 600 seconds or so. The downside to this is that the changes to web site settings will have a delay before going into effect.

b) also enable Apache graceful restarts

Refer to this Plesk Help Center article: How to enable/disable Apache graceful restart in Plesk.

Note, and this is important, you shouldn't enable the graceful restarts unless you have prolonged the Apache restart interval and unless you have an active watchdog service (your own custom one or the one provided by Plesk).

An Apache graceful restart can take time. If there is a graceful restart in progress (but not completed yet) and another graceful restart is attempted, Apache will fail and remain shut down. Hence the importance of a prolonged restart period *and* an active watchdog service present on your system.