Choose which alerts go to Slack or a webhook, and whether they page the on-call.
Use Warrn as an alert router when one source produces many alerts but only some of them should reach a particular Slack channel, webhook, or on-call responder.For example, one CloudWatch integration can receive every alarm from an AWS account while an alert rule sends only production database alarms to #database-alerts and an operations webhook. The rule can deliver those notifications without paging anyone.
Source integration: where the alert entered Warrn, such as CloudWatch, Sentry, or the Incoming API.
Match conditions: the alert name, severity, tags, or metadata that identify the alerts you want.
External notifications: the Slack channels or webhooks that receive matching alerts.
On-call paging: whether matching alerts continue into the team’s paging flow.
External notifications and paging are independent. A matching rule can notify Slack and page, notify without paging, page without an external notification, or suppress the alert entirely.
Open the team or service that owns the destination, go to Integrations, and add one of the following:
Slack OAuth to select one or more channels from a connected Slack workspace.
Slack Webhook to send to the channel associated with a Slack incoming webhook.
Outgoing Webhook to send alert JSON to an HTTP endpoint.
Configure the destination, choose its allowed severity levels, enable it, and use Test to verify the connection. See Slack and Outgoing Webhooks for integration-specific setup.Create the destination on the same team as the alert rule, or on a service owned by that team. A team rule can explicitly select destinations from any of that team’s services, including a different service from the alert’s source. Destinations belonging to another team are unavailable.
2
Set the destination to Routing rules only
In the destination’s Configuration tab, find Alert delivery and select Routing rules only.This keeps the destination quiet until an enabled alert rule explicitly selects it. Use All team or service alerts only when the destination should receive the team’s normal alert stream without needing a rule.
Set a destination to Routing rules only before selecting it in an alert rule
3
Create the alert rule
Open the team, go to On-Call, expand Alert Rules, and select Add Rule.
Give the rule a name that describes the route.
Under Integration scope, select the incoming integration that produces the alerts. Choose All integrations when the rule should also evaluate manual alerts and alerts from any source.
Add match conditions for the alert name, severity, tags, or metadata.
Set External notifications to Send only to selected destinations, then select the Slack channels or webhooks that should receive matching alerts.
Under On-call paging, choose Do not page anyone for a notification-only route, or keep normal paging enabled when responders should also be paged.
A rule that routes matching CloudWatch alerts to Slack and a webhook without paging
4
Test the rule before saving
Open Test this rule in the rule editor. Paste a representative alert payload, select its source integration, and evaluate the draft.The evaluator shows whether the current conditions match and what the rule would do. It uses your unsaved changes and does not create an alert, send a notification, or page anyone.
5
Simulate the complete routing flow
From the team’s On-Call tab, open Simulate alert routing. Provide a sample alert, choose its source integration, and select the time at which the alert should arrive.The simulator evaluates the team’s alert rules, outgoing destinations, routing rules, schedules, and escalation policies. It then shows the resulting flow without creating an alert or contacting anyone.
The simulator traces external delivery and paging as separate outcomes
6
Optionally verify with a live alert
After the simulation looks correct, trigger one matching alert from the source if you want to verify the complete delivery path.A notification-only alert appears under Alerts → Routed. Open the destination’s Observability tab to confirm delivery or inspect an error.
Every outgoing Slack or webhook destination has its own delivery mode:
Mode
When the destination receives an alert
Use it for
Routing rules only
An enabled alert rule matches and explicitly selects this destination
Focused channels, downstream automation, and notification-only routes
All team or service alerts
The destination is part of the normal team or service notification stream, unless a matching rule replaces the destination list
General alert channels that should receive most alerts
When a rule uses the normal destinations, Warrn uses the alert’s service configuration first. For each integration type configured for automatic delivery on that service, the corresponding team defaults are excluded. Automatic team destinations fill in integration types that the service does not configure. Send only to selected destinations replaces this inherited list with the rule’s explicit selections, including any selected service-owned destinations within the team.
The destination must be enabled, and its severity filter still applies in both modes. Selecting a destination in a rule does not bypass a destination that is disabled or configured to reject that severity.
This configuration sends matching RDS alarms to Slack and an operations webhook without paging:
Setting
Value
Integration scope
Production CloudWatch
Conditions
Name starts with database-, and metadata cloudwatch_namespace equals AWS/RDS
External notifications
Send only to selected destinations
Destinations
#database-alerts, Operations webhook
On-call paging
Do not page anyone
An alert that does not match this rule continues to the rules below it. If no alert rule matches, Warrn uses the team’s normal notification and paging configuration.
External notifications: use the normal destinations, send only to selected destinations, or send no external notification.
On-call paging: continue into the normal paging flow or do not page anyone.
Choosing Do not page anyone stops on-call escalation. It does not silence destinations selected under External notifications. If the alert should go nowhere, set external notifications to send nothing or use the Suppress Alert action.
Routes apply when an alert fires or fires again. Rule-selected Slack channels and outgoing webhooks do not receive later acknowledgement or resolution events through the route. Do not rely on routed messages to stay synchronized with the alert’s lifecycle; open the alert in Warrn to see its current state.
Add Map customers or Map customer pools to the matching alert rule to link affected customers using names, external IDs, or a fixed selection of existing records. Creation is optional and off by default. The draft evaluator and full routing simulator show planned links and creations without saving records.Customer mapping also works when Do not page anyone is selected. Fully suppressed alerts skip mapping. See Map customer impact for setup and examples.
Alerts routed without paging live in Alerts → Routed. Warrn keeps them out of the Active and Open queues so those views stay focused on alerts that need a responder. Routed alerts remain available in All Alerts and search.Each routed alert shows whether its source is still firing and records the matched rule and delivery outcome in its timeline.
