Comprehensive upgrade instructions can be found in docs/UPGRADE. As
with any major administration task, it is strongly suggested that you back up your complete
installation before beginning. Upgrading is a two-step process:
The code must first be upgraded. This will involve downloading a new copy of OJS, or downloading and installing a patch file. Both the full OJS package and the relevant patch file are available from http://pkp.sfu.ca/ojs_download.
The database must be upgraded. This can be done using the
tools/upgrade.php script.
See docs/UPGRADE for complete instructions.
If the installation has been customized in any way, it will be necessary to ensure that the customizations are properly migrated to the new version:
Use the standard diff and patch tools. To generate a patch file describing the modifications you have made to an installation, generate a diff file against a stock version of that installation. For example, if you are upgrading from OJS 2.1.1 to OJS 2.3:
$ diff -u /path/stock-ojs-2.1.1 /path/modified-ojs-2.3-install > mods.diff
This will generate a file called mods.diff. Review this file;
these changes may need to be transferred into the upgraded installation.
Ensure that any schema changes you make are properly reflected in the XML database
schema descriptor(s) in dbscripts/xml (e.g.
dbscripts/xml/ojs_schema.xml). During upgrades, these schema
files are applied and any added or modified columns may be reverted.