Upgrading Debian from version 12 (bookworm) to 13 (trixie) is an operation that should be performed in a repeatable and predictable way, especially on servers and containers (for example Proxmox LXC or virtual machines). Below you will find a simple guide and ready-to-use commands to download and run the upgrade script.

Before running the upgrade: create a backup or snapshot. In Proxmox, the best option is vzdump or a snapshot. On bare metal, at minimum back up /etc, applications, and databases.

• Proxmox LXC / VM: backup using vzdump or create a snapshot.
• Server: backup /etc, /var/www, databases (MySQL/PostgreSQL), and SSL certificates.

Script download:

https://soban.pl/bash/upgrade_to_debian13.sh

1) Backup before upgrade (examples)

Example backup in Proxmox (run on Proxmox host, replace CTID/VMID):

vzdump 101 --mode snapshot --compress zstd --storage local

Example simple filesystem backup on a server (this does not replace a full snapshot, but it’s better than nothing):

tar czf /root/backup_before_upgrade.tar.gz /etc /var/www /root

2) Download the script (wget / curl)

The easiest way is to use wget. If the wget command does not work even though the package is installed, use the full path /usr/bin/wget.

Variant A (standard wget):

apt update
apt install -y wget
cd /root
wget -O upgrade_to_debian13.sh https://soban.pl/bash/upgrade_to_debian13.sh
chmod +x upgrade_to_debian13.sh

Variant B (wget with full path – useful if PATH is broken):

apt update
apt install -y wget
cd /root
/usr/bin/wget -O upgrade_to_debian13.sh https://soban.pl/bash/upgrade_to_debian13.sh
chmod +x upgrade_to_debian13.sh

Variant C (curl):

apt update
apt install -y curl
cd /root
curl -fsSL -o upgrade_to_debian13.sh https://soban.pl/bash/upgrade_to_debian13.sh
chmod +x upgrade_to_debian13.sh

3) Script help (parameters)

Before running the upgrade, display available parameters and usage examples:

cd /root
./upgrade_to_debian13.sh --help

4) Upgrade Debian 12 → Debian 13 (system only)

If you are currently running Debian 12 (bookworm) and want to perform a system upgrade:

cd /root
./upgrade_to_debian13.sh

The script will create a backup of /etc/apt/sources.list, switch repositories to trixie, run apt update and apt full-upgrade, and finally execute autoremove and autoclean.

5) Auto-detect PHP/nginx and update if needed

If the container or VM is running a web stack and you want the script to automatically detect PHP usage (nginx + fastcgi_pass) and upgrade PHP and nginx if necessary:

cd /root
./upgrade_to_debian13.sh --auto

6) Force PHP and nginx upgrade (PHP-FPM socket fix)

If you want to force installation or upgrade of PHP and automatically fix nginx configuration to use the correct PHP-FPM socket:

cd /root
./upgrade_to_debian13.sh --with-php --with-nginx --php-version 8.2

This command installs PHP 8.2 (php-fpm and common modules) and replaces old PHP-FPM socket paths in nginx configuration with /run/php/php8.2-fpm.sock. Then it runs nginx -t and reloads or restarts services.

7) Already running Debian 13? PHP/nginx only mode

If the system is already running Debian 13 (trixie) and you only want to upgrade PHP and nginx without modifying system repositories:

cd /root
./upgrade_to_debian13.sh --php-nginx-only --with-php --with-nginx --php-version 8.2

8) Dry-run mode (test mode)

If you want to see what the script will do without making any changes:

cd /root
./upgrade_to_debian13.sh --auto --dry-run

9) Troubleshooting: wget installed but not working

If apt reports wget is installed but the shell shows command not found, it is usually a PATH issue. The easiest workaround is to use the full path: /usr/bin/wget.

echo "$PATH"
command -v wget || true
ls -l /usr/bin/wget || true
/usr/bin/wget --version || true

Summary

This solution provides a convenient way to upgrade Debian 12 → Debian 13 and optionally fix common PHP/nginx issues after upgrade (PHP-FPM socket paths, nginx config testing, and service restart). Always create a backup before upgrading and start by running --help to review available options.

Script: https://soban.pl/bash/upgrade_to_debian13.sh

Artykuł Automatic upgrade Debian 12 → Debian 13 with optional PHP and nginx update pochodzi z serwisu soban.

Expanding disk space in Linux virtual machines is a key aspect of server system management. In this article, we show how to effectively increase disk space using LVM and fdisk tools, based on real system data.

Preliminary Preparations

Before making changes to partitions and volumes, it is important to check the current state of the disks in the system. We will use the lsblk command to identify available disks and partitions.

lsblk

Here is an example of the lsblk command output on a machine:

NAME                      MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
loop0                       7:0    0 55.7M  1 loop /snap/core18/2829
sda                         8:0    0   42G  0 disk
├─sda1                      8:1    0  512M  0 part /boot/efi
├─sda2                      8:2    0    1G  0 part /boot
└─sda3                      8:3    0 40.5G  0 part
  └─ubuntu--vg-ubuntu--lv 253:0    0 78.5G  0 lvm  /
sdb                         8:16   0  350G  0 disk
└─sdb1                      8:17   0   60G  0 part
  └─ubuntu--vg-ubuntu--lv 253:0    0 78.5G  0 lvm  /
sr0                        11:0    1 1024M  0 rom

Creating Snapshots

Before making changes to disk configurations, it is advisable to create a snapshot of the LVM volumes to ensure data can be restored in case of unexpected issues.

lvcreate -L 20G -s -n my_snapshot /dev/ubuntu-vg/ubuntu-lv

Modifying Partitions

Next, we proceed to modify the partitions using fdisk. We remove the existing partition and then create a new one that utilizes the entire available space on disk sdb.

fdisk /dev/sdb

Saving Changes

After properly configuring the partitions, we use the w command in fdisk to save the changes and update the partition table.

Command (m for help): w

Executing pvscan

After modifying the partitions, we execute the pvscan command so the system can update information about available physical volumes.

pvscan

Configuring LVM

After saving changes to the partition table, we need to update the LVM configuration to include the new disk space. We use the lvextend command with automatic file system resizing.

lvextend -l +100%FREE /dev/ubuntu-vg/ubuntu-lv -r

Summary

Expanding disk space on a Linux virtual machine enhances performance and the availability of storage space. Thanks to the steps described, managing disk space in systems using LVM becomes simpler and more efficient.

Artykuł Expanding Storage Space in Linux: Step-by-Step Guide using LVM and fdisk pochodzi z serwisu soban.