Skip to content

Maintenance Windows

Maintenance windows suppress alert processing during planned maintenance. While a window is active, alerts matching its label matchers are still ingested and stored, but they do not trigger routing, notification dispatch, or investigation creation — so planned work doesn't page anyone or spawn noise.

How They Work

When an alert arrives, Alga checks it against every enabled maintenance window whose time range covers the current moment. If the alert's labels satisfy the window's label_matchers, the alert is suppressed for the duration of the window.

A window is active when all of the following hold:

  • enabled is true
  • The current time is between start_time and end_time
  • The alert's labels match every entry in label_matchers

Window Fields

FieldDescription
nameHuman-readable name (e.g., "Database Migration")
start_timeWhen suppression begins (RFC3339)
end_timeWhen suppression ends (RFC3339); must be after start_time
label_matchersMap of label key/value pairs an alert must match to be suppressed
enabledWhether the window is active (default true)
created_byEmail of the user who created the window

An empty label_matchers map matches every alert during the window.

Creating a Window

  1. Go to Maintenance in the sidebar
  2. Create a window with a name, start and end time, and label matchers (e.g., namespace: database)
  3. Matching alerts are suppressed until the window ends

You can disable a window early by setting enabled to false, or delete it.

Relationship to Routing

Maintenance windows are a suppression mechanism alongside silenced routing rules. Use silenced rules for permanent, label-based noise dropping, and maintenance windows for temporary, time-boxed suppression around planned changes.

API Endpoints

MethodPathAuthPermissionDescription
GET/api/v1/maintenance-windowsSessionroutes:readList windows (supports ?enabled=true)
POST/api/v1/maintenance-windowsSessionroutes:writeCreate window
GET/api/v1/maintenance-windows/{id}Sessionroutes:readGet window
PUT/api/v1/maintenance-windows/{id}Sessionroutes:writeUpdate window
DELETE/api/v1/maintenance-windows/{id}Sessionroutes:writeDelete window

See Also

  • Routing — alert routing rules and silenced rules
  • Alerts — alert ingestion and lifecycle

Released under the MIT License.