Debian 13 – unmet dependencies and held packages during apt upgrade – Fix & Prevention

📖 ~1 min read

Table of contents

1. Symptom & Impact
2. Environment & Reproduction
3. Root Cause Analysis
4. Quick Triage
5. Step-by-Step Diagnosis
6. Solution – Primary Fix
7. Solution – Alternative Approaches
8. Verification & Acceptance Criteria
9. Rollback Plan
10. Prevention & Hardening
11. Related Errors & Cross-Refs
12. References & Further Reading

Symptom & Impact

apt upgrade fails with unmet dependencies and leaves packages unconfigured.

Environment & Reproduction

Often seen after mixed repositories, holds, or interrupted upgrades.

cat /etc/os-release
apt-mark showhold
sudo apt update

Root Cause Analysis

Package solver cannot resolve a consistent set due to version constraints.

Quick Triage

Identify held packages and broken state before forcing installs.

apt-mark showhold
sudo apt --fix-broken install -y
sudo dpkg --audit

Step-by-Step Diagnosis

Use dry-runs and review pinning rules to find conflicting constraints.

sudo apt upgrade --dry-run
sudo apt full-upgrade --dry-run
grep -R 'Pin:' /etc/apt/preferences*

Solution – Primary Fix

Repair dpkg state, clear invalid holds, then run full-upgrade.

sudo dpkg --configure -a
sudo apt --fix-broken install -y
sudo apt-mark unhold $(apt-mark showhold)
sudo apt update
sudo apt full-upgrade -y

Solution – Alternative Approaches

Disable third-party sources temporarily and retry dependency resolution.

sudo sed -i 's/^deb/# deb/g' /etc/apt/sources.list.d/*.list
sudo apt update
sudo apt install PACKAGE -y

Verification & Acceptance Criteria

No held packages and no broken dependency output remain.

sudo apt full-upgrade -y
apt-mark showhold
sudo dpkg --audit

Rollback Plan

Pin or reinstall known-good versions for critical services.

apt-cache policy PACKAGE
sudo apt install PACKAGE=VERSION -y
sudo apt-mark hold PACKAGE

Prevention & Hardening

Keep repositories minimal and avoid unsupported suite mixing.

grep -R '^deb ' /etc/apt/sources.list /etc/apt/sources.list.d
sudo apt update && sudo apt upgrade -y

Related Errors & Cross-Refs

Related errors include held broken packages and impossible dependency situations.

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 pinning and package dependency troubleshooting docs.