Cannot upgrade from 8.2.8 to 9.0.5

Steps to reproduce
1. Have an owncloud installation on version 8.2.8 (according to the admin-panel) (in folder owncloud-8.2.8)
2. Download the owncloud-9.0.5.tar.bz2 file, extract it to owncloud-9.0.5
3. copy the config/config.php from the old installation to the new installation
4. run su www-data -c './occ upgrade' inside the new installation

Expected behaviour
The installation should have been successfully upgraded.

Actual behaviour

root@moon:/var/www/owncloud-9.0.5# su www-data -c './occ upgrade'
ownCloud or one of the apps require upgrade - only a limited number of commands are available
You may use your browser or the occ upgrade command to do the upgrade
Set log level to debug
Exception: Updates between multiple major versions and downgrades are unsupported.
Update failed
Maintenance mode is kept active
Reset log level

Server configuration
Operating system: Debian Jessie
Web server: Scaleway C1
Database: mysql Ver 14.14 Distrib 5.5.52, for debian-linux-gnu (armv7l)
PHP version: PHP 5.6.26-0+deb8u1
ownCloud version (see ownCloud admin page): 8.2.28
Updated from an older ownCloud or fresh install: updated from an older installation
Special configuration (external storage, external authentication, reverse proxy, server-side-encryption): nothing fancy

Hi,

see https://doc.owncloud.org/server/9.1/admin_manual/maintenance/manual_upgrade.html how to do a correct upgrade. If your previous installed version is really 8.2.8 you won't see that message when following these steps.

You also shouldn't used per version directories as moving the datadir is (like from owncloud-8.2.8 to owncloud-9.0.5) is currently unsupported.

First of all, thank you very much for your reply.

At the moment, I'm working with an empty datadir. I used to just have a symlink in data to the actual location of the files, but for the migration I left that out thinking that it would make things easier.

When I go back to the old installation, I can still see the 8.2.8 in the admin panel. How can I find out what version I really have?

Hi,

your "real" ownCloud version can be found in the version option of your config/config.php.

Ok, I found the problem. I had copied my config.php from an older 8.1 installation because I didn't realize that it would be updated during upgrades.

Using the config.php file from the 8.2 installation let me do the upgrade.

Thanks again!