Upgrade old proxmox 5

[Mikel Martinez]

Hello,
I have an old Proxmox 5 installation on two hosts that I need to upgrade. The problem is that, even though I have a subscription, the Buster packages have been deleted, so I can't upgrade.
Is there another location where the repository is located?

This is the error I'm getting:

apt update
Hit:1 http://archive.debian.org/debian buster InRelease
Hit:2 http://archive.debian.org/debian-security buster/updates InRelease
Ign:3 https://enterprise.proxmox.com/debian/pve buster InRelease
Err:4 https://enterprise.proxmox.com/debian/pve buster Release
404 Not Found
Reading package lists... Done
E: The repository 'https://enterprise.proxmox.com/debian/pve buster Release' does not have a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.

 

[fl0moto]

Hi Mikel,
this should be what you're looking for:

Thread 'New Archive CDN for End-of-Life (EOL) Releases'

Jan 9, 2026

Today, we announce the availability of a new archive CDN dedicated to the long-term archival of our old and End-of-Life (EOL) releases.
Effective immediately, this archive hosts all repositories for releases based on Debian 10 (Buster) and older.

The archive is reachable via the following URLs:

• http://archive.proxmox.com/
• https://archive.proxmox.com/

To use the archive for an EOL release, you will need to change the domain in the apt repository configuration files in /etc/apt/sources.list or inside /etc/apt/sources.list.d/ from...

• t.lamprecht

• 

Cheers

 

[leesteken]

Boot-related things changes between 5 and 6 or 6 and 7, I can't remember the details. You'll have to follow the upgrade guides from 5 to 6, 6 to 7, 7 to 8 and 8 to 9, making some manual changes each time. If might be much easier to backup everything and install PVE 9 fresh, configure it and restore VM and CTs from backups. I would imagine that you also have new hardware (as PVE 6 is over 6 years old) for a new install.

 

[Mikel Martinez]

Hi Mikel,
this should be what you're looking for:

Thread 'New Archive CDN for End-of-Life (EOL) Releases'

Jan 9, 2026

Today, we announce the availability of a new archive CDN dedicated to the long-term archival of our old and End-of-Life (EOL) releases.
Effective immediately, this archive hosts all repositories for releases based on Debian 10 (Buster) and older.

The archive is reachable via the following URLs:

• http://archive.proxmox.com/
• https://archive.proxmox.com/

To use the archive for an EOL release, you will need to change the domain in the apt repository configuration files in /etc/apt/sources.list or inside /etc/apt/sources.list.d/ from...

• t.lamprecht

• 

Cheers

Thank you so much, that's exactly what I was looking for.