# Debian Upgrade auf neuen Release
Quelle: [https://www.cyberciti.biz/faq/update-upgrade-debian-9-to-debian-10-buster/](https://www.cyberciti.biz/faq/update-upgrade-debian-9-to-debian-10-buster/)
## Upgrade Debian 9 to Debian 10 Buster
The procedure is as follows:
1. Backup your system.
2. Update existing packages and reboot the Debian 9.x system.
3. Edit the file /etc/apt/sources.list using a text editor and replace each instance of **stretch** with **buster**.
4. Update the packages index on Debian Linux, run: **sudo apt update**
5. Prepare for the operating system upgrade, run: **sudo apt upgrade**
6. Finally, update Debian 9 to Debian 10 buster by running: **sudo apt full-upgrade**
7. Reboot the Linux system so that you can boot into Debian 10 Buster
8. Verify that everything is working correctly.
Let us see all command in details.
## Step 1. Backup your system
It is crucial to backup all data and system configurations. Cloud-based VMs can be quickly backup and restore using snapshots. I use [rsnapshot](https://www.cyberciti.biz/faq/linux-rsnapshot-backup-howto/), which is the perfect solution for making backups on the local or remote servers. [Check os version in Linux](https://www.cyberciti.biz/faq/how-to-check-os-version-in-linux-command-line/):
`lsb_release -a`
Sample outputs:
```
No LSB modules are available.
Distributor ID: Debian
Description: Debian GNU/Linux 9.9 (stretch)
Release: 9.9
Codename: stretch
```
Note down the [Linux kernel version](https://www.cyberciti.biz/faq/find-print-linux-unix-kernel-version/) too:
`uname -mrs`
Sample outputs:
```
Linux 4.9.0-9-amd64 x86_64
```
## Step 2. Update installed packages
Type the following [apt command](https://www.cyberciti.biz/faq/ubuntu-lts-debian-linux-apt-command-examples/ "See Linux/Unix apt command examples for more info") or [apt-get command](https://www.cyberciti.biz/tips/linux-debian-package-management-cheat-sheet.html "See Linux/Unix apt-get command examples for more info"):
`sudo apt update sudo apt upgrade sudo apt full-upgrade sudo apt --purge autoremove`
OR
`sudo apt-get update sudo apt-get upgrade sudo apt-get full-upgrade sudo apt-get --purge autoremove`
[Reboot the Debian 9.x stretch](https://www.cyberciti.biz/faq/howto-reboot-linux/) to apply the kernel and other updates:
`sudo reboot`
## Step 3. Update /etc/apt/sources.list file
Before starting the upgrade you must reconfigure APT’s source-list files. To view current settings using the [cat command](https://www.cyberciti.biz/faq/linux-unix-appleosx-bsd-cat-command-examples/ "See Linux/Unix cat command examples for more info"):
`cat /etc/apt/sources.list`
Sample outputs:
```
deb http://cdn-aws.deb.debian.org/debian stretch main
deb http://security.debian.org/debian-security stretch/updates main
deb http://cdn-aws.deb.debian.org/debian stretch-updates main
```
The stretch indicates that we are using an older version. Hence, we must change all the references in this file from Stretch to Buster using a text editor such as vim:
`vi /etc/apt/sources.list`
I prefer to use sed tool, but first backup all config files using the [cp command](https://www.cyberciti.biz/faq/cp-copy-command-in-unix-examples/ "See Linux/Unix cp command examples for more info"):
`sudo cp -v /etc/apt/sources.list /root/ sudo cp -rv /etc/apt/sources.list.d/ /root/ sudo sed -i 's/stretch/buster/g' /etc/apt/sources.list sudo sed -i 's/stretch/buster/g' /etc/apt/sources.list.d/* ### see updated file now ### cat /etc/apt/sources.list `
APT source-list files updated to use buster### Updating the package list
Simply run:
`sudo apt update`
## Step 4. Minimal system upgrade
A two-part process is necessary to avoid the removal of large numbers of packages that you want to keep. Therefore, first run the following:
`sudo apt upgrade`
Just follow on-screen instructions. During the upgrade process, you may get various questions, like “Do you want to restart the service? ” OR “keep or erase config options” and so on.
And:
## Step 5. Upgrading Debain 9 to Debian 10
In addition, minimum upgrades we need to do full upgrades to finish the whole Debian 9 to Debian 10 update process. This is the main part of the upgrade. In other words, execute the following command to perform a complete upgrade of the system, installing the newest available versions of all packages, and resolving all possible dependency:
`sudo apt full-upgrade`
[Reboot the Linux system](https://www.cyberciti.biz/faq/ssh-restart-linux-system-reboot-command/) to boot into Debian Linux 10 buster, issue:
`sudo reboot`
## Step 6. Verification
It is time to confirm the upgrade. Run:
`uname -r lsb_release -a`
Sample outputs:
```
No LSB modules are available.
Distributor ID: Debian
Description: Debian GNU/Linux 10 (buster)
Release: 10
Codename: buster
```
Finally, clean up outdated packages using the [apt command](https://www.cyberciti.biz/faq/ubuntu-lts-debian-linux-apt-command-examples/ "See Linux/Unix apt command examples for more info")/[apt-get command](https://www.cyberciti.biz/tips/linux-debian-package-management-cheat-sheet.html "See Linux/Unix apt-get command examples for more info"):
`sudo apt --purge autoremove`
## Conclusion
And there you have it. We have successfully upgraded to Debian Linux 10. Debian project also posted an in-depth guide [here](https://www.debian.org/releases/buster/amd64/release-notes/ch-upgrading.en.html) that explains other issues one might face during installation.