I am doing the 1.3 -> 1.4 upgrade with databaseupgrade in command line.
The updater page in piwik tells:
It is also recommended for high traffic Piwik servers to momentarily disable visitor Tracking and put the Piwik User Interface in maintenance mode.
The linked page How to - Analytics Platform - Matomo tells me to put piwik in maintenance mode. But when doing so the commandline job fails:
tracking@somehost:~/httpdocs$ php /path/to/site/httpdocs/index.php -- "module=CoreUpdater" <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html> <head> <title>Piwik › Error</title> ... <p>Piwik is in scheduled maintenance. Please come back later.</p>
So the maintenance mode make the upgrade impossible…!?