Note: You are currently viewing documentation for Moodle 1.9. Up-to-date documentation for the latest stable version is available here: Database migration.
Migration and third party modules
If you have third party modules installed, not yet ready yet for the UTF-8 migration, you'll be warned about these on this page. You need to either disable them or install a later version. The migration script can only run once, so if you have problematic third party modules disabled, you will need to use an alternative method such as converting all files to UTF-8 with a database dump.
If you run your site in one language only, select this option to save a lot of time on the migration. Otherwise, Moodle will figure out how to do the migration for every piece of data, based on the language of the user, course and your Moodle site.
The migration process
Since the migration is a process which causes heavy processor and disk load and can take a long time to perform, you should choose when to upgrade carefully. As an indication, Moodle.org had about 3 million bits of text and took 2.5 hours on a very fast dual-opteron server.
During the migration process, you'll see a progress bar which updates every now and then. Let it go all the way to 100%. If the migration is interrupted for some reason (browser closed or network failure) don't worry - just wait for a while to make sure the process is finished on the server (you might check processor load, caused by your webserver), and then start the migration again. The process is smart enough to take up where it left off and you'll see messages about this. However, starting the migration script while a former process of the script is still running might cause data corruption.
The migration process places your Moodle site in maintenance mode, so non-admins cannot login. Once the migration process has started, it needs to finish completely before non-admins can login. Your Moodle site will then automatically come out of maintenance mode.