slainer68/railsfrance.org — comment on commit 82f90d86356b99901eddc2ca9baa8a30b2f57ec9
File: config/settings/development.yml.sample line 15
By slainer68:

OK, that's because the default Redis config is no auth, and empty string is considered as a valid password, therefore an auth exception occurs when using the sample config with a default Redis config.