Zitat (Laurent BARDET (Laurent))[Tue Mar 30 17:06:54.330180 2021] [php7:error] [pid 4724] [client 160.xx.xxx.xxx:58887] PHP Fatal error: Uncaught InvalidArgumentException: Identifier "ilAppEventHandler" is not defined. in /var/www/html/ilias/libs/composer/vendor/pimple/pimple/src/Pimple/Container.php:96\nStack trace:\n#0 /var/www/html/ilias/Modules/OrgUnit/classes/Positions/UserAssignment/class.ilOrgUnitUserAssignment.php(86): Pimple\\Container->offsetGet()\n#1 /var/www/html/ilias/Modules/OrgUnit/classes/Positions/UserAssignment/class.ilOrgUnitUserAssignment.php(96): ilOrgUnitUserAssignment->raiseEvent()\n#2 /var/www/html/ilias/Modules/OrgUnit/classes/Positions/UserAssignment/class.ilOrgUnitUserAssignment.php(77): ilOrgUnitUserAssignment->create()\n#3 /var/www/html/ilias/Services/Database/classes/class.ilDBUpdate.php(496) : eval()'d code(33): ilOrgUnitUserAssignment::findOrCreateAssignment()\n#4 /var/www/html/ilias/Services/Database/classes/class.ilDBUpdate.php(496): eval()\n#5 /var/www/html/ilias/Services/Database/classes/class.ilDBUpdate.php(363): ilDBUpdate->applyUpdateNr()\n#6 /var/www/html/ilias/setup/classes/class.ilSetupGUI.php(2690): ilDBUpdate in /var/www/html/ilias/libs/composer/vendor/pimple/pimple/src/Pimple/Container.php on line 96, referer: https://pprod-inform.intradef.gouv.fr/setup/setup.php?cmd=db&client_id=eadterre&back=clientlist
However, the timestamp (Tue Mar 30 17:06) indicates that this happened later that day. Did you run the update steps again around that time? If yes, this might be the error causing the problems.
I could not find an existing bugreport in Mantis regarding this error. You may want to open a new report at mantis.ilias.de. Please provide all the info there too (update step number, error message, exact ILIAS version, etc.).