Problem: cups Printserver Reaches MaxClients

Problem

You printserver drops connections and might run at 100% CPU usage.

Environment

You will notice following entries in logfiles:

W [08/Sep/2020:10:07:10 +0200] Max clients reached, holding new connections...
W [08/Sep/2020:10:07:10 +0200] Max clients reached, holding new connections...
W [08/Sep/2020:10:07:10 +0200] Max clients reached, holding new connections...

Solution

Increase the number of maximum allowed clients. As of now this is not possible by ucr variables until this bug is fixed.

Step 1

Edit the template file. Note: Editing a template file is usually not recommended as the file might not get overwritten during a future update.
Edit
vi /etc/univention/templates/files/etc/cups/cupsd.conf

Look for the line with MaxClients and remove the hash sign in front of it. It should look like this:
MaxClients 300

Step 2

Write the changes to the configuration file:
ucr commit /etc/cups/cupsd.conf

Step 3

Restart cupsd
systemctl restart cupsd