When you already work on a problem, more alerts about it only add noise. Silence the failed check, for example during an ongoing incident or a deployment, and Dash0 holds back its notifications for a fixed time.

A silence covers one failed check. The check rule does not change, and Dash0 keeps recording the failed check, so its history stays complete.

Tip

To open the Failed Checks View, choose Alerting and then Failed checks in the Dash0 navigation menu. You can also go to the Failed Checks View directly from here.

Silence a Failed Check

Open the Failed Checks View and click a failed check to open its detail sidebar.
Click Silence.
Choose a Silence duration: 30 minutes, 1 hour, 2 hours, 4 hours, or Custom.
Optionally, enter a Reason so your team knows why the check is silenced.
Click Save.

A custom duration is a whole number of minutes, hours, or days, up to 7 days.

A new silence can take up to 3 minutes to take effect. Until then, notifications for the failed check can still go out.

You can also silence a resolved failed check. The silence applies if the check fails again before the silence ends.

Any member who can see a failed check can silence it. The same members can extend or end any silence.

What a Silence Covers

A silence covers one failed check. If the check fails again for the same resource while the silence is active, the silence covers that failure too.

When you save a change to the check rule, Dash0 tracks the next failures as a new failed check. The silence does not cover the new failed check, and its notifications go out. This also applies when you disable and enable the check rule.

While a silence is active:

Dash0 does not send the first notification, severity changes, or reminders for the failed check.
Dash0 still records the failed check. It stays in the Failed Checks View with a Silenced tag.
Automations with a Failed Check trigger still run. Their Silenced checks option includes silenced checks, excludes them, or uses only silenced checks. The default is to include them.
Automations with a Failed Check Notification trigger do not run, because Dash0 sends no notification.

When the failed check resolves, a notification channel gets the resolved notification only if Dash0 sent a notification for this failed check to it before. If the silence held back every notification, the channel gets no resolved notification, even after the silence ends.

When a silence ends and the check still fails, Dash0 does not send a notification immediately. The next notification goes out at the next reminder or severity change. If the notification channel sends no reminders, only a severity change sends the next notification.

See Which Failed Checks Are Silenced

The Failed Checks View has a Silenced column. Hover over the tag to see when the silence ends, or that it already ended.
Filter on the Silenced column to find failed checks that a silence covered at any time in the selected time range.
The timeline of a failed check shows stripes over the time that a silence covered it. Hover over a striped time to see a Silenced tag.
The detail sidebar of a silenced failed check lists up to four silences that cover it, and when each one ends. A link opens the rest in the Silences Hub.

Manage Silences in the Silences Hub

The Silences Hub lists the active and completed silences of the current dataset. Open it from Settings, under Connectivity, or click Manage Silences in the Failed Checks View.

Each silence shows its status, scope, reason, schedule, and creator. Search silences, or filter them by All, Active, or Completed.

The Silences Hub keeps a completed silence for at least 30 days after it ends.

Extend a Silence

Open the actions menu of an active silence and click Extend. In the detail sidebar of the failed check, you can also click the clock icon next to a silence.
Choose a duration in Extend by. Dash0 adds this time to the current end of the silence.
Click Save.

If the current end is less than 3 minutes away, notifications can go out for a short time until the extension takes effect. The confirmation after you save shows until when.

End a Silence Early

To end one silence, open its actions menu in the Silences Hub and click Unsilence, then confirm. In the detail sidebar, you can also click the bell icon next to the silence, then confirm.
To end every silence that covers one failed check, click Silenced in its detail sidebar, click Unsilence, and confirm.

The silence ends now and stays in the list as completed. Notifications for the failed check can stay held back for up to 3 minutes.

Use Agent0 with Silences

In a chat, Agent0 can:

List your silences.
End every silence that covers one failed check.
Propose a new silence, or propose to extend or shorten a silence. A proposal takes effect only when you apply it.

Agent0 does not end silences from automations.

Silence Limits

Limit	Value
Longest silence, counted from its start, including extensions	7 days
Active silences per organization, across all datasets	1000
Reason	1050 characters
Time until a new silence takes effect	Up to 3 minutes

When your organization reaches the limit of active silences, Dash0 rejects a new silence. End a silence before you create another. The limit counts silences in all datasets.

Silence Failed Checks