Change freeze windows define time periods during which changes should not occur. They are part of the operational guardrails system and work alongside deployment policies.
Create freeze windows from the OpsTrails console at Guardrails → Change Freeze Windows.
| Field | Type | Required | Description |
|---|---|---|---|
name | string | required | A descriptive name for the freeze window |
startsAt | datetime | required | When the freeze begins (ISO 8601) |
endsAt | datetime | required | When the freeze ends (ISO 8601) |
subjects | string[] | optional | Limit to specific subjects (e.g., "production"). Empty = all subjects. |
sources | string[] | optional | Limit to specific sources (e.g., "//github.com/acme/api"). Empty = all sources. |
types | string[] | optional | Limit to specific event types (e.g., "deployment"). Empty = all matched types. |
severities | string[] | optional | Limit to specific severities (e.g., "CRITICAL"). Empty = all severities. |
notificationChannels | channel[] | optional | Notification channels to alert on violation. Email is always sent. |
enabled | boolean | optional | Whether the freeze is active. Defaults to true. |
A freeze window moves through the following statuses:
startsAt. The freeze is scheduled but not yet active.startsAt and endsAt. Events matching the filters will trigger a violation.endsAt and no violation occurred.When an event is recorded during an active freeze window and matches the configured filters, the freeze is marked as Violated. The first matching event triggers notifications to all linked channels. Subsequent violations during the same freeze do not send additional notifications.
Editing a violated freeze window resets its status. If the freeze is still active after editing, it can be violated again.
Use the optional filter fields — subjects, sources, types, and severities — to narrow which events trigger a violation. When a filter is empty, all values match. For example, setting subjects to ["production"] means only events with subject “production” will trigger the freeze. See Core Concepts for definitions of event fields.
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