📖 ~1 min read
Table of contents
Symptom & Impact
`apt full-upgrade` fails with unmet dependencies and blocked package transitions.
Environment & Reproduction
Common after manual pinning or partial upgrades.
cat /etc/debian_version
sudo apt-mark showhold
sudo apt update
sudo apt full-upgrade
Root Cause Analysis
Held packages and pin priorities prevent resolver from completing required upgrades.
Quick Triage
Enumerate holds, pins, and broken package state.
sudo apt-mark showhold
grep -RIn 'Pin:' /etc/apt/preferences /etc/apt/preferences.d 2>/dev/null
sudo apt -f install -y
Step-by-Step Diagnosis
Use resolver debug output to identify blockers.
sudo apt-get -o Debug::pkgProblemResolver=yes dist-upgrade -s
sudo dpkg --audit
sudo tail -n 120 /var/log/apt/term.log

Solution – Primary Fix
Remove unnecessary holds and normalize package state.
Still having issues? Our IT Solutions & Services team can diagnose and resolve this for you. Get in touch for a free consultation.
for p in $(apt-mark showhold); do sudo apt-mark unhold $p; done
sudo dpkg --configure -a
sudo apt -f install -y
sudo apt full-upgrade -y

Solution – Alternative Approaches
Disable third-party repositories temporarily to isolate conflicts.
sudo mkdir -p /var/tmp/apt-sources-backup
sudo cp -a /etc/apt/sources.list.d /var/tmp/apt-sources-backup/
sudo sed -i 's/^deb/#deb/g' /etc/apt/sources.list.d/*.list
sudo apt update
Verification & Acceptance Criteria
No holds remain and full-upgrade simulation succeeds.
sudo apt-mark showhold
sudo apt-get check
sudo apt full-upgrade -s
Rollback Plan
Reapply required holds after compatibility validation.
sudo apt-mark hold
sudo cp -a /var/tmp/apt-sources-backup/sources.list.d/* /etc/apt/sources.list.d/
sudo apt update
Prevention & Hardening
Track holds centrally and review before maintenance windows.
apt-mark showhold > /var/tmp/held-packages.txt
apt-cache policy | head -n 120
Related Errors & Cross-Refs
Related to obsolete repositories, stale pin files, and partial upgrades.
Related tutorial: View the step-by-step tutorial for Debian 13.
View all Debian 13 tutorials on the Tutorials Hub →
Browse all common problems & solutions on the Tutorials Hub.
References & Further Reading
Debian apt policy and pinning guidance.
Need Expert Help?
If you cannot resolve this yourself, our team offers hands-on Server Management, Managed IT Services, and flexible Support Plans. Contact us today — we respond within one business day.