3. From Alertmanager drop-down, select an external Alertmanager to create and manage silences for the external data source. Otherwise, keep the default option of Grafana.
4. Click **New Silence** to open the Create silence page.
5. In **Silence start and end**, select the start and end date to indicate when the silence should go into effect and expire.
6. Optionally, in **Duration**, specify how long the silence is enforced. This automatically updates the end time in the **Silence start and end** field.
7. In the **Name** and **Value** fields, enter one or more _Matching Labels_. Matchers determine which rules the silence will apply to. For more information, see [how label matching works]({{< relref "../fundamentals/annotation-label/labels-and-label-matchers/" >}}).