Restoring backup(v0.16) to new server (v0.21) - owncloud update failed

Maintenance
3

To “fix” my issue, I manually upgraded ownCloud from v8.1.1 to v8.2.10 by:

  1. backup /home/user-data/own cloud
  2. get ownCloud v8.2.10 tarball from https://owncloud.org/changelog/#latest8.2
  3. extract tarball and replace /usr/local/lib/owncloud
  4. create symlink to /home/user-data/owncloud/config.php at /usr/local/lib/owncloud/config
    Note: ensure owner of link is www-data
  5. cd to /usr/local/lib/owncloud/
  6. sudo -u www-data php occ upgrade

After above is done successfully, there will be no issue running mailinabox setup again which will upgrade owncloud to v9.1.1
7. sudo mailinabox

Whew