Fixed Ubuntu's unattended-upgrades restarting Exasol systemd services

Detail name	Value
Changelog Number	25803
Type	Bug
Status	Resolved
Affected Versions	Exasol 8.34.0, Exasol 8.29.9
Fix Versions	Exasol 2025.1.0, C4 4.19.9, C4 4.28.0
Resolution Date	2025-06-26

Description

Ubuntu’s unnattended-upgrades perform regular automated package updates. With the recent Ubuntu 24.04 changes these updates now also restart all the systemd system services (user services are unaffected). This affects Exasol systemd services that run the entire Exasol stack, causing unnecessary downtime.

Workaround

Prevent updates restarting Exasol services by running these commands inside of every node as root (outside of the COS container):

mkdir -p /etc/needrestart/conf.d
cat << EOF > /etc/needrestart/conf.d/exasol.conf
\$nrconf{override_rc}{qr(^c4_cloud_command\.service\$)} = 0;
\$nrconf{override_rc}{qr(^c4\.service\$)} = 0;
\$nrconf{override_rc}{qr(^exasol-admin-ui\.service\$)} = 0;
EOF

Fix

c4 now prevents updates from restarting Exasol services by adding rules into “needrestart” configuration during installation.