Comment 1 for bug 1712103

Appears to be because there is no /var/log/dmesg:

ubuntu@above-ox:~$ ls /var/log/
alternatives.log cloud-init-output.log kern.log.1 syslog.2.gz
apt dist-upgrade lastlog syslog.3.gz
auth.log dpkg.log lxd syslog.4.gz
auth.log.1 fontconfig.log ntpstats sysstat
btmp fsck syslog unattended-upgrades
cloud-init.log kern.log syslog.1 wtmp

(on MAAS deployments at least).