Maintenance mode was introduced in Unleash 4.22.0.
Unleash maintenance mode is a feature that lets administrators put Unleash into a mostly read-only mode. While Unleash is in maintenance mode:
- Unleash users can not change any configuration settings
- Unleash's APIs will not allow you to persist any changes
However, any metrics sent to Unleash from client SDKs are still processed, so this mode does not have any effect on client SDKs.
Maintenance mode is particularly useful during important events when any accidental or deliberate changes the feature/strategy configurations could lead to issues.
Maintenance mode configuration
Maintenance mode is controlled from the "maintenance" section of the Unleash admin configuration page.
When maintenance mode is enabled, a warning banner appears at the top of the Unleash dashboard, indicating that any changes made during this period will not be saved and may result in errors.
Maintenance mode and scheduled jobs
When maintenance mode is enabled all internal jobs performed by Unleash such as updating metrics and statistics are paused. When maintenance mode is toggled back to disabled later, all scheduled jobs are resumed.
Maintenance mode and read-only DB user
When maintenance mode is enabled most DB operations are suspended so you can use even read-only DB user. There's one exception though. Unleash DB user role needs a DELETE and UPDATE permission on the unleash_session table.
GRANT DELETE ON unleash_session TO my_db_role;
GRANT UPDATE ON unleash_session TO my_db_role;