ubuntu2mint / ubuntu-to-mint-convert-v3

High-risk, best-effort in-place conversion script that keeps Ubuntu as the base OS while adding Linux Mint repositories + Mint desktop/tooling to approximate a Linux Mint system without a full reinstall.

This project is intended for experienced Linux admins who understand APT, repo pinning, display managers, and rollback strategies.

🟥 UNSUPPORTED + PROBABLY DUMB (READ THIS FIRST)
There is no guaranteed safe way to convert Ubuntu to Linux Mint in-place and preserve all corporate software/agents.
EDR/MDM/VPN/compliance tooling may break and require re-enrollment.
A clean install (or a second disk/VM test) is the recommended approach.

The script enforces an interactive “I understand” gate during convert and also requires --i-accept-the-risk.

What this does

• Detects supported Ubuntu bases:
  • Ubuntu 24.04 (noble) → targets Linux Mint 22.x (default 22.3 “zena”)
  • Ubuntu 22.04 (jammy) → targets Linux Mint 21.x (default 21.3 “virginia”)
• Adds the Linux Mint package repository (packages.linuxmint.com)
• Keeps Ubuntu repos for the underlying base system
• Installs Mint meta-packages (desktop + tooling) and configures:
  • LightDM as default display manager
  • slick-greeter as greeter
  • Default desktop session based on --edition
• Applies conservative APT pinning:
  • Ubuntu remains default for overlapping base packages
  • Mint desktop stack is pinned high to avoid mixed-version dependency breakage
• Includes guardrails:
  • APT/dpkg lock detection
  • best-effort dpkg/apt repair (--no-auto-fix to disable)
  • simulation plan + safety checks (removal thresholds + critical package protection)
  • disables third-party sources by default (with allowlist heuristics for common corp repos)
  • backup + rollback support
  • post-conversion validation report written into the backup directory

What this does not do

• It does not replace your OS identity with Mint in a fully supported way.
• It does not guarantee your machine remains compliant in managed enterprise environments.
• It does not guarantee perfect package resolution—APT may still want to remove packages.
• Rollback restores /etc/apt, but may not remove packages installed during conversion (use snapshots/Timeshift for full reversion).
• This script is LightDM-first, which implies X11 sessions; it does not attempt to force Wayland.

Requirements

• Ubuntu 24.04 (noble) or 22.04 (jammy)
• Root access (sudo)
• Working APT and dpkg state (the script can attempt basic remediation)
• Internet access to:
  • Ubuntu mirrors (or your corporate mirror)
  • packages.linuxmint.com
• Recommended:
  • Timeshift snapshot configured
  • Full-disk backup or VM snapshot

Quick start

1) Clone and run doctor checks

git clone https://github.com/LINUXexpert-org/ubuntu2mint.git
cd ubuntu2mint
sudo bash ubuntu-to-mint-convert-v3.sh doctor

2) (Optional) Run plan mode (dry-run)

Plan mode simulates the APT changes and writes a log under /var/log/ubuntu-to-mint/.

sudo bash ubuntu-to-mint-convert-v3.sh plan --edition cinnamon

Plan mode uses a temporary APT environment (it does not modify your system’s APT sources). It creates a temporary Mint keyring by downloading and extracting the linuxmint-keyring package.

Plan mode is for decision support. It does not modify /etc/apt or install Mint repos onto your live system.

3) Run conversion

sudo bash ubuntu-to-mint-convert-v3.sh convert --i-accept-the-risk --edition cinnamon

You can skip the secondary interactive confirmation prompts with --yes:

sudo bash ubuntu-to-mint-convert-v3.sh convert --i-accept-the-risk --edition cinnamon --yes

The big red unsupported disclaimer gate is still required during convert even with --yes.

4) Reboot and validate

After conversion:

1. Reboot

2. Login via LightDM and confirm your chosen session loads

3. Validate:

   • VPN connectivity (GlobalProtect, etc.)
   • EDR/MDM agents + compliance posture (CrowdStrike Falcon, etc.)
   • corporate certificates / SSO
   • NetworkManager
   • printers
   • smartcards / YubiKey
   • camera/audio

Usage

sudo bash ubuntu-to-mint-convert-v3.sh doctor [--no-auto-fix]
sudo bash ubuntu-to-mint-convert-v3.sh plan [options]
sudo bash ubuntu-to-mint-convert-v3.sh convert --i-accept-the-risk [options]
sudo bash ubuntu-to-mint-convert-v3.sh rollback /root/ubuntu-to-mint-backup-YYYYMMDD-HHMMSS

Options

Desktop / targets

• --edition cinnamon|mate|xfce Desktop edition meta-package to install (default: cinnamon).

• --target <mint_codename> Override the Mint target codename. Allowed targets depend on your Ubuntu base:

  • Ubuntu noble: zena, zara, xia, wilma
  • Ubuntu jammy: virginia, victoria, vera, vanessa

• --mint-mirror <url> Override Mint mirror base URL (default: http://packages.linuxmint.com)

Safety / APT behavior

• --keep-ppas Do not disable third-party APT sources (not recommended). Default behavior disables PPAs and most third-party repos during conversion and moves them into the backup folder. Some common enterprise repos may be automatically allowlisted.

• --with-recommends Allow installation of recommended packages (default: off for safety).

• --max-removals N Abort if APT simulation removes more than N packages (default: 40).

• --yes Skip most interactive prompts. (Does not bypass the convert disclaimer gate or --i-accept-the-risk requirement.)

• --no-auto-fix Disable best-effort dpkg/apt repair pre-flight.

Keyring handling

• --overwrite-keyring If /usr/share/keyrings/linuxmint-repo.gpg exists, overwrite it.

• --recreate-keyring Back up and delete the keyring then recreate it.

Flavor / meta package conflict handling

• --no-purge-flavor Disable best-effort purging of conflicting Ubuntu flavor packages (e.g., ubuntucinnamon-*) that can cause session crashes/login loops.

Safety model (important)

Guardrails included to reduce “brick your system” outcomes:

• Refuses to run unless on supported Ubuntu bases

• Detects and blocks active APT/dpkg locks

• Attempts to repair basic dpkg/apt broken states (unless --no-auto-fix)

• Disables PPAs by default during conversion (unless --keep-ppas)

• Runs an APT simulation and aborts if:

  • APT wants to remove critical packages (e.g., sudo, systemd, network-manager, kernel meta packages)
  • too many removals are detected (default threshold 40)

• Creates a backup directory for rollback

• Post-conversion validation writes a report into the backup directory (always created)

Logs and backups

Logs

• Main log:

  • /var/log/ubuntu-to-mint/ubuntu-to-mint-YYYYMMDD-HHMMSS.log

• Plan logs:

  • /var/log/ubuntu-to-mint/plan-YYYYMMDD-HHMMSS.txt

Backup directory

During convert, a backup directory is created, e.g.:

• /root/ubuntu-to-mint-backup-YYYYMMDD-HHMMSS/

Contains:

• /etc/apt backup

• package inventories (apt-manual, holds, dpkg list)

• enabled systemd services list

• snap/flatpak lists (if installed)

• disabled third-party sources (if disabled)

• post-convert validation report:

  • post-convert-validation.txt

Rollback

Rollback restores /etc/apt and any disabled sources from the backup:

sudo bash ubuntu-to-mint-convert-v3.sh rollback /root/ubuntu-to-mint-backup-YYYYMMDD-HHMMSS
sudo apt-get update
sudo apt-get -f install

Rollback restores APT configuration but may not remove packages installed during conversion. For full restoration use Timeshift / snapshot / backup.

Troubleshooting

APT update fails after conversion

• Check:

  • /etc/apt/sources.list.d/official-package-repositories.list
  • Mint mirror reachability
  • corporate proxy settings

• If needed:

  • rollback using the backup directory

Desktop won’t start / login loop

• Boot to a TTY (Ctrl+Alt+F3)

• Inspect:

  • journalctl -b -p err
  • user session logs: ~/.xsession-errors

• Reinstall key desktop components:

  • sudo apt-get install --reinstall lightdm slick-greeter cinnamon-session cinnamon-settings-daemon muffin

Key retrieval / keyserver issues

This version avoids keyservers by default. It prefers:

• a locally installed linuxmint-keyring package, or
• downloading the latest linuxmint-keyring_*.deb from the Mint mirror and extracting the keyring

If your existing keyring is corrupt:

• rerun with --recreate-keyring or --overwrite-keyring

Known dpkg overwrite conflict (mintupdate)

Some environments will hit a file conflict between mintupdate and software-properties-gtk over an icon file. The script installs the Mint stack with a guarded dpkg overwrite option to prevent conversion from halting.

Corporate VPN/EDR breaks

• Reinstall using corporate-provided packages
• Re-enroll if required
• Validate kernel modules, certificate stores, and PAM stack

Security & compliance considerations

If this is a corporate-managed device:

• Get explicit approval before modifying base OS repositories
• Confirm your organization’s standard OS images and compliance requirements
• Expect that security tooling may detect drift and require remediation

License

Copyright (C) 2026 LINUXexpert.org

This project is licensed under the GNU General Public License v3.0. See the LICENSE file or the header in ubuntu-to-mint-convert-v3.sh.

Disclaimer

This project is provided as-is. You assume all risk for system instability, data loss, or compliance impact. Always have a tested restore path before running.