Receiver Configuration

The Alertmanager Config Secret contains the configuration of an Alertmanager instance that sends out notifications based on alerts it receives from Prometheus.

This section assumes familiarity with how monitoring components work together. For more information about Alertmanager, see this section.

Creating Receivers in the Rancher UI

Prerequisites:
  • The monitoring application needs to be installed.

  • If you configured monitoring with an existing Alertmanager Secret, it must have a format that is supported by Rancher’s UI. Otherwise you will only be able to make changes based on modifying the Alertmanager Secret directly. Note: We are continuing to make enhancements to what kinds of Alertmanager Configurations we can support using the Routes and Receivers UI, so please file an issue if you have a request for a feature enhancement.

  1. Go to the cluster where you want to create receivers. Click Monitoring -> Alerting -> AlertManagerConfigs.

  2. Click Create.

  3. Enter a Name for the new AlertmanagerConfig.

  4. Click Create.

  5. After creating the AlertManagerConfig, click it to add a receiver.

  6. Click Add Receiver.

  7. Enter a Name for the receiver.

  8. Configure one or more providers for the receiver. For help filling out the forms, refer to the configuration options below.

  9. Click Create.

Result: Alerts can be configured to send notifications to the receiver(s).

Receiver Configuration

The notification integrations are configured with the receiver, which is explained in the Prometheus documentation.

Native vs. Non-native Receivers

By default, AlertManager provides native integration with some receivers, which are listed in this section. All natively supported receivers are configurable through the Rancher UI.

For notification mechanisms, such as Telegram, that are not natively supported by AlertManager, integration is achieved using the webhook receiver. A list of third-party drivers providing such integrations can be found here. Access to these drivers, and their associated integrations, is provided through the Alerting Drivers app. Once enabled, configuring non-native receivers can also be done through the Rancher UI.

Currently the Rancher Alerting Drivers app provides access to the following integrations:

  • Microsoft Teams, based on the prom2teams driver.

  • Telegram, based on the Sachet driver.

The following types of receivers can be configured in the Rancher UI:

The custom receiver option can be used to configure any receiver in YAML that cannot be configured by filling out the other forms in the Rancher UI.

Slack

Field Type Description

URL

String

Enter your Slack webhook URL. For instructions to create a Slack webhook, see the Slack documentation.

Default Channel

String

Enter the name of the channel that you want to send alert notifications in the following format: #<channelname>.

Proxy URL

String

Proxy for the webhook notifications.

Enable Send Resolved Alerts

Bool

Whether to send a follow-up notification if an alert has been resolved (e.g. [Resolved] High CPU Usage).

Email

Field Type Description

Default Recipient Address

String

The email address that will receive notifications.

Enable Send Resolved Alerts

Bool

Whether to send a follow-up notification if an alert has been resolved (e.g. [Resolved] High CPU Usage).

SMTP options:

Field Type Description

Sender

String

Enter an email address available on your SMTP mail server that you want to send the notification from.

Host

String

Enter the IP address or hostname for your SMTP server. Example: smtp.email.com.

Use TLS

Bool

Use TLS for encryption.

Username

String

Enter a username to authenticate with the SMTP server.

Password

String

Enter a password to authenticate with the SMTP server.

PagerDuty

Field Type Description

Integration Type

String

Events API v2 or Prometheus.

Default Integration Key

String

For instructions to get an integration key, see the PagerDuty documentation.

Proxy URL

String

Proxy for the PagerDuty notifications.

Enable Send Resolved Alerts

Bool

Whether to send a follow-up notification if an alert has been resolved (e.g. [Resolved] High CPU Usage).

Opsgenie

Field Description

API Key

For instructions to get an API key, refer to the Opsgenie documentation.

Proxy URL

Proxy for the Opsgenie notifications.

Enable Send Resolved Alerts

Whether to send a follow-up notification if an alert has been resolved (e.g. [Resolved] High CPU Usage).

Opsgenie Responders:

Field Type Description

Type

String

Schedule, Team, User, or Escalation. For more information on alert responders, refer to the Opsgenie documentation.

Send To

String

Id, Name, or Username of the Opsgenie recipient.

Webhook

Field Description

URL

Webhook URL for the app of your choice.

Proxy URL

Proxy for the webhook notification.

Enable Send Resolved Alerts

Whether to send a follow-up notification if an alert has been resolved (e.g. [Resolved] High CPU Usage).

Custom

The YAML provided here will be directly appended to your receiver within the Alertmanager Config Secret.

Teams

Enabling the Teams Receiver for Rancher Managed Clusters

The Teams receiver is not a native receiver and must be enabled before it can be used. You can enable the Teams receiver for a Rancher managed cluster by going to the Apps page and installing the rancher-alerting-drivers app with the Teams option selected.

  1. In the Rancher UI, go to the cluster where you want to install rancher-alerting-drivers and click Apps.

  2. Click the Alerting Drivers app.

  3. Click the Helm Deploy Options tab.

  4. Select the Teams option and click Install.

  5. Take note of the namespace used as it will be required in a later step.

Configuring the Teams Receiver

  1. To configure the Teams receiver, update its ConfigMap. The following example is a minimal Teams receiver configuration:

     [Microsoft Teams]
     connector: https://your-teams-webhook-url
  2. After you update the configuration, follow the instructions in Creating Receivers in the Rancher UI to add the receiver. Use the example below to form your URL. Make sure to replace <namespace> with the namespace of the rancher-alerting-drivers app:

     url: http://rancher-alerting-drivers-prom2teams.<namespace>.svc:8089/v2/connector

SMS

Enabling the SMS Receiver for Rancher Managed Clusters

The SMS receiver is not a native receiver and must be enabled before it can be used. You can enable the SMS receiver for a Rancher managed cluster by going to the Apps page and installing the rancher-alerting-drivers app with the SMS option selected.

  1. In the upper left corner, click ☰ > Cluster Management.

  2. On the Clusters page, go to the cluster where you want to install rancher-alerting-drivers and click Explore.

  3. In the left navigation bar, click

  4. Click the Alerting Drivers app.

  5. Click the Helm Deploy Options tab

  6. Select the SMS option and click Install.

  7. Take note of the namespace used as it will be required in a later step.

Configuring the SMS Receiver

The SMS receiver can be configured by updating its ConfigMap. For example, the following is a minimal SMS receiver configuration.

providers:
  telegram:
    token: 'your-token-from-telegram'

receivers:
- name: 'telegram-receiver-1'
  provider: 'telegram'
  to:
    - '123456789'

When configuration is complete, add the receiver using the steps in this section.

Use the example below as the name and URL, where:

  • the name assigned to the receiver, e.g. telegram-receiver-1, must match the name in the receivers.name field in the ConfigMap, e.g. telegram-receiver-1

  • ns-1 in the URL is replaced with the namespace where the rancher-alerting-drivers app is installed

name: telegram-receiver-1
url http://rancher-alerting-drivers-sachet.ns-1.svc:9876/alert

Telegram

Enabling the Telegram Receiver for Rancher Managed Clusters

The Telegram receiver is not a native receiver. You must enable it before it can be used. You can enable the Telegram receiver for a Rancher-managed cluster by going to the Apps page and installing the rancher-alerting-drivers app with the Telegram option selected:

  1. In the upper left corner, click ☰ > Cluster Management.

  2. On the Clusters page, go to the cluster where you want to install rancher-alerting-drivers and click Explore.

  3. In the left navigation bar, click on Apps.

  4. Click the Alerting Drivers app.

  5. Click on Install.

  6. In the page that opens next, make sure that Enable SMS checkbox is selected. Telegram notifications require you to enable SMS.

  7. Take note of the namespace used as it will be required in a later step.

Test the Configuration by Configuring a PrometheusRule

To test your Telegram setup, create a PrometheusRule that continuously raises alerts.

NOTE

This rule is intended only to test if Telegram alerts work as expected. Do not leave it on after testing is completed.

  1. In the left navigation menu, click Monitoring.

  2. Click Advanced.

  3. Click PrometheusRules  Create.

  4. Select a namespace to place the rule in and name the rule appropriately.

  5. Set the group name to test. Use this value later when you create a Route in the AlertManagerConfig.

  6. Under Alerting Rules click Add.

  7. Set an appropriate Alert Name.

  8. To trigger the alert immediately and continuously, enter the following PromQL Expression: vector(1).

  9. Under Labels, click Add Label. Enter the key test and value alert. This key-value pair will also be used later.

Configure an AlertManagerConfig

Configure an AlertManagerConfig to contain the Receiver and Route configuration for the PrometheusRule created above:

  1. Click Monitoring  Alerting, and open AlertManagerConfigs.

  2. Click Create

Create a Receiver in AlertManagerConfig

  1. Choose a namespace from the dropdown and set an appropriate name.

  2. Click Create.

  3. Open the newly created AlertManagerConfig and click ⋮ > Edit Config.

  4. Click Add Receiver.

  5. Select Webhook from the list on the Create Receiver in AlertmanagerConfig page.

  6. Name the webhook, and click Add Webhook.

  7. In the Select Webhook Type dropdown, select SMS. This will automatically populate the Target field as http://rancher-alerting-drivers-sachet.cattle-monitoring-system.svc:9876/alert. If you installed the Alerting Drivers in a namespace other than cattle-monitoring-system, the target URL will reflect that.

  8. Click Create.

Create a Route in AlertManagerConfig

  1. Click ⋮ > Edit Config.

  2. Click Route.

  3. In the dropdown, select the Receiver you just created.

  4. In the Labels to Group Alerts By field, type test.

  5. Under Waiting and Intervals, set Group Wait to 1s and Group Interval to 10s. This triggers frequent alerts. Change the values as appropriate.

  6. Under Matchers click Add Matcher. Enter test in the Name field and alert in the Value field. From the Match Type dropdown, select MatchEqual.

  7. Click Save.

Configuring the Telegram Receiver

You can configure the Telegram receiver by updating the rancher-alerting-drivers-sachet ConfigMap in the cattle-monitoring-system namespace. For example, the following is a minimal Telegram receiver configuration:

providers:
  telegram:
    token: <your-token-from-telegram>

receivers:
- name: 'cattle-monitoring-system/test-amc/prom2tel'
  provider: 'telegram'
  to:
    - '123456789'

To obtain a Telegram token, setup a Telegram bot. Refer to the official Telegram guide for details. After you finish configuring the receiver, add it.

Name the receiver <namespace>/<alertmanagerconfig-name>/<receiver-name>. Enter 123456789 as a placeholder for the Telegram user ID to send the notifications to. To find your Telegram ID, check the Telegram userinfo bot.

You should now receive Telegram notifications to the user ID. If you don’t receive notifications, please check if there are any errors reported in the Pod for the Deployment rancher-alerting-drivers-sachet under the cattle-monitoring-system namespace.

Configuring Multiple Receivers

By editing the forms in the Rancher UI, you can set up a Receiver resource with all the information Alertmanager needs to send alerts to your notification system.

It is also possible to send alerts to multiple notification systems. One way is to configure the Receiver using custom YAML, in which case you can add the configuration for multiple notification systems, as long as you are sure that both systems should receive the same messages.

You can also set up multiple receivers by using the continue option for a route, so that the alerts sent to a receiver continue being evaluated in the next level of the routing tree, which could contain another receiver.

Example Alertmanager Configs

Slack

To set up notifications via Slack, the following Alertmanager Config YAML can be placed into the alertmanager.yaml key of the Alertmanager Config Secret, where the api_url should be updated to use your Webhook URL from Slack:

route:
  group_by: ['job']
  group_wait: 30s
  group_interval: 5m
  repeat_interval: 3h
  receiver: 'slack-notifications'
receivers:
- name: 'slack-notifications'
  slack_configs:
  - send_resolved: true
    text: '{{ template "slack.rancher.text" . }}'
    api_url: <user-provided slack webhook url here>
templates:
- /etc/alertmanager/config/*.tmpl

PagerDuty

To set up notifications via PagerDuty, use the example below from the PagerDuty documentation as a guideline. This example sets up a route that captures alerts for a database service and sends them to a receiver linked to a service that will directly notify the DBAs in PagerDuty, while all other alerts will be directed to a default receiver with a different PagerDuty integration key.

The following Alertmanager Config YAML can be placed into the alertmanager.yaml key of the Alertmanager Config Secret. The service_key should be updated to use your PagerDuty integration key and can be found as per the "Integrating with Global Event Routing" section of the PagerDuty documentation. For the full list of configuration options, refer to the Prometheus documentation.

route:
 group_by: [cluster]
 receiver: 'pagerduty-notifications'
 group_interval: 5m
 routes:
  - match:
      service: database
    receiver: 'database-notifcations'

receivers:
- name: 'pagerduty-notifications'
  pagerduty_configs:
  - service_key: 'primary-integration-key'

- name: 'database-notifcations'
  pagerduty_configs:
  - service_key: 'database-integration-key'

Example Route Config for CIS Scan Alerts

While configuring the routes for rancher-cis-benchmark alerts, you can specify the matching using the key-value pair job: rancher-cis-scan.

For example, the following example route configuration could be used with a Slack receiver named test-cis:

spec:
  receiver: test-cis
  group_by:
#    - string
  group_wait: 30s
  group_interval: 30s
  repeat_interval: 30s
  match:
    job: rancher-cis-scan
#    key: string
  match_re:
    {}
#    key: string

For more information on enabling alerting for rancher-cis-benchmark, see this section.

Trusted CA for Notifiers

If you need to add a trusted CA to your notifier, follow the steps in this section.