Comment 3 for bug 1801910

I have met same case with you also I'm using proxmox. Should like the image of Proxmox provided for us diffent a bit with normal OS. My laptop using Ubuntu 18.04 but no problem with the rsyslog. It still is version rsyslogd 8.32.0.

Rsyslog is included in all major distributions. So you do not necessarily need to take care of where packages can be found - they are “just there”. Unfortunately, the distros provide often rather old versions. This is especially the case for so-called enterprise distributions.

So to fix this, I have still newest version of rsyslog then the issue has solved.

sudo apt-get install -y software-properties-common # Provide add-apt-repository
sudo add-apt-repository ppa:adiscon/v8-stable
sudo apt-get update
sudo apt-get install rsyslog

Let's run again:
# /etc/cron.daily/logrotate