Beginning with the 2016-08-27 release, Canvas will require PostgreSQL version 9.3 or newer. If you are running an older version of PostgreSQL, Canvas will detect it on boot up, and raise an appropriate error. It's suggested that you upgrade your Postgres installation ahead of time. Documentation to do so can be found at
https://www.postgresql.org/docs/9.3/static/upgrading.html. You're more than welcome to upgrade to 9.3, 9.4, or 9.5.
Cody Cutrer
Software Engineer
Instructure