Debian Testing Forky

Porfirio Páiz — Mon, 02 Feb 2026 02:15:00 -0600

So I have another Lenovo ThinkPad, this one is a T450 and it is currently running Debian 13.

On this post I will be upgrading from Debian 13.3 to Debian Testing (Forky).

Pre-upgrade Process

Confirm the installed Debian version just to make sure where we are starting from:

cat /etc/debian_version

Which returns:

13.3

Gather System Information

This command gives us more information about the current version installed on our device:

lsb_release -a

Which returns:

Distributor ID: Debian
Description:    Debian GNU/Linux 13 (trixie)
Release:        13
Codename:       trixie

This is another alternative to get even more information about the installed system version:

cat /etc/os-release

Which returns:

PRETTY_NAME="Debian GNU/Linux 13 (trixie)"
NAME="Debian GNU/Linux"
VERSION_ID="13"
VERSION="13 (trixie)"
VERSION_CODENAME=trixie
DEBIAN_VERSION_FULL=13.3
ID=debian
HOME_URL="https://www.debian.org/"
SUPPORT_URL="https://www.debian.org/support"
BUG_REPORT_URL="https://bugs.debian.org/"

Storage Analysis

Before upgrading, I wanted to know how much storage space I have used since Debian 13.3 was installed on my T450.

Analyze APT Cache

I ran this command to measure the total storage space used:

sudo du -sh /var/cache/apt/archives/

Which returned the following:

8.3G /var/cache/apt/archives/

Since I installed Debian 13.3 on this device, I have downloaded 8.3 GB of packages.

sudo head -n 1 /var/log/installer/syslog

Which returns:

Sep  4 04:37:28 syslogd started: BusyBox v1.30.1

Meaning that Debian 13.3 was installed on September 4, 2025 at 04:37:28 UTC.

sudo tune2fs -l /dev/mapper/taylor--vg-root | grep 'Filesystem created:'

Which returns:

Filesystem created:       Wed Sep  3 23:10:05 2025

Meaning that the root filesystem was created on September 3, 2025 at 23:10:05 UTC.

sudo tune2fs -l /dev/sda2 | grep 'Filesystem created:'

Which returned the following:

Filesystem created:       Wed Sep  3 22:41:58 2025

Meaning that the /boot filesystem was created on September 3, 2025 at 22:41:58 UTC.

Package Inventory

Something important to me before upgrading is to make a list of all the packages currently installed.

Methods to List Packages

Selection List: Saves a basic list to packagesInstalled.
```
dpkg --get-selections > packagesInstalled
```
Detailed Query: Includes status, version, and architecture.
```
dpkg-query -l > dpkgQuery-l
```

Binary Names Only: Useful for clean, one-per-line lists.

dpkg-query -f '${binary:Package}\n' -W > dpkgQuery-f_binPac

Manual Selections: Lists packages specifically requested by the user.
```
apt-mark showmanual > manuallyInstalled
```

The Upgrade Process

OK... enough nostalgia for the moment; this is where the fun begins!

Update Current System

As it is, I need to make sure that my system is fully up to date:

sudo apt-get update
sudo apt-get upgrade
sudo apt-get dist-upgrade

Modify Package Sources

First, make a backup of your current configuration:

sudo cp /etc/apt/sources.list /etc/apt/sources.list.orig

Then, update the file to switch the codename to Forky:

cd /etc/apt/
sudo sed -i.bak '/^deb-src\|^deb/ s/trixie/forky/g' /etc/apt/sources.list

Perform the Full Upgrade

Update the repository data:

sudo apt update

Check for upgradable packages:

sudo apt list --upgradable

We will upgrade first without installing new packages:

sudo apt upgrade --without-new-pkgs

Once this is completed, we can fully upgrade our system:

sudo apt full-upgrade

Conclusion

Once this process was completed, I was able to reboot my system and run Debian Testing (Forky) on my Lenovo ThinkPad T450 without having to reinstall from scratch.

porfirio's blog - forky

Debian Testing Forky

Pre-upgrade Process

Gather System Information

Storage Analysis

Analyze APT Cache

Package Inventory

Methods to List Packages

The Upgrade Process

Update Current System

Modify Package Sources

Perform the Full Upgrade

Conclusion