Dirk's Tech Findings

CUPS: Service start not possible due to AppArmor

Publication date: 2025-08-20

Issue: CUPS cannot start, AppArmor messages in system log

There are many messages in the system logs that are telling that CUPS could not start. Reason appears to be a restriction imposed by AppArmor. This happened on a fresh installation of Debian Trixie after its public release.

Messages look like the following one:

Aug 20 15:34:52 myhost kernel: audit: type=1400 audit(1755696892.115:159): apparmor="DENIED" operation="create" class="net" info="failed protocol match" error=-13 profile="/usr/sbin/cupsd" pid=3329 comm="cupsd" family="unix" sock_type="stream" protocol=0 requested="create" denied="create" addr=none

Solution: Deactivate AppArmor for that service

After installing AppArmor utils, the restriction can be removed:

apt install apparmor-utils
aa-complain cupsd

Hint towards the solution

Back to topic list...