VMware ESXi and vSphere Cluster Management

How to Acknowledge Triggered Alarms in VMware vSphere

Learn how to acknowledge triggered VMware vSphere alarms, verify acknowledgment details, understand alarm actions, and distinguish acknowledgment from Reset to Green.

A VMware vSphere alarm tells you that a configured condition or event threshold has been met. Acknowledgment is the operator action used after reviewing that alert. It records that a user has seen the alarm and taken ownership of the response, while the alarm condition may remain active.

This procedure is performed in the vSphere Client, the web-based administrative interface for vCenter-managed resources. vCenter Server is the management platform that maintains the inventory, alarms, events, permissions, and monitoring workflows for objects such as hosts, virtual machines, clusters, datastores, and datacenters.

What a Triggered Alarm and Acknowledgment Mean

A Triggered Alarm is an alarm currently raised because its configured condition is true. For example, a datastore capacity threshold may have been exceeded, or a host connectivity condition may be failing.

The alarm state describes the current health level reported by the alarm. Common states include:

Normal: The configured triggering condition is no longer active.
Warning: The monitored condition has reached a cautionary threshold.
Alert: The monitored condition has reached a more serious threshold or event state.

Acknowledgment is separate from the alarm state. It records that an administrator has seen and accepted responsibility for the alert. An alarm can therefore remain in Warning or Alert status after it has been acknowledged.

Prerequisites and Access Requirements

The alarm must be managed through vCenter Server and the vSphere Client.
Your account must be able to view the relevant inventory object and its triggered alarms.
Your assigned vCenter role may need a privilege to acknowledge alarms.
A separate privilege may be required to reset alarms manually.
You should understand the vSphere inventory hierarchy well enough to identify the object that owns the alarm.

If an action is unavailable, do not assume that the alarm is healthy. The selected object may be wrong, the alarm may no longer be active, or your account may lack the required privilege. Review vCenter role assignments and permissions with the appropriate administrator. For related access concepts, see Access Control System and Assign Permissions.

Where to Find Triggered Alarms

Alarm visibility depends on the inventory scope you select. First select the affected inventory object, which is a managed vCenter entity such as a vCenter object, datacenter, cluster, ESXi host, virtual machine, datastore, or network object.

Open the vSphere Client and sign in to the appropriate vCenter Server.
Select the affected object in the vCenter inventory.
Open the Monitor area.
Open Issues.
Select Triggered Alarms.

The list at a parent level may include alarms associated with that scope, while a child object may show only alarms associated with the child. If an expected alarm is not visible, check the affected object's parent and child inventory levels.

Procedure: Acknowledge a Triggered Alarm

Select the relevant object in the vCenter inventory. Examples include a datastore, host, virtual machine, cluster, or datacenter.
Go to Monitor > Issues > Triggered Alarms.
Locate the active alarm entry.
Select the alarm row.
Open the alarm context menu or the available action control.
Choose Acknowledge.
Confirm the action if the client asks for confirmation.
Review the row to verify that the acknowledgment status, time, and user information are recorded.

The exact appearance of menus can vary between vSphere Client releases and according to your permissions. The essential workflow remains selecting the affected object, opening its triggered-alarm view, selecting the active alarm, and using its acknowledgment action.

How to Verify Acknowledgment

After acknowledging the alarm, review the fields available in the triggered-alarm list. Useful fields include:

Alarm name: Identifies the alarm definition that was triggered.
Current status: Shows whether the alarm remains Normal, Warning, or Alert.
Affected object: Identifies the host, VM, datastore, cluster, or other object associated with the alarm.
Acknowledged status: Indicates whether a user has acknowledged the alarm.
Acknowledged time: Records when the acknowledgment occurred.
Acknowledged by: Records the account or user that performed the acknowledgment.

Use the acknowledgment metadata as part of the incident record. Also review the original alarm state and triggering condition. Acknowledgment confirms that someone took ownership; it does not confirm that the condition has cleared.

Acknowledgment Versus Alarm State

Think of an alarm as having two related but different dimensions:

Condition or alarm state: What the monitored resource is reporting now.
Acknowledgment state: Whether an administrator has reviewed and taken ownership of the raised alarm.

For example, a host connectivity alarm can remain in Alert status if the host is still unreachable. An operator may acknowledge it after opening an incident and assigning an investigation. The alarm remains visible as triggered because the connectivity condition still fails.

In general, an alarm returns to Normal when its configured triggering condition clears. Acknowledging the alarm does not force that transition.

Effect on Alarm Actions

An alarm action is an automated response configured for an alarm. Examples include sending a notification, running a script, or initiating another operational response.

Acknowledging an active alarm prevents further configured alarm actions from being executed for that acknowledged alarm while it remains acknowledged. This is useful when an operator has reviewed the alert and does not want repeated notifications for an incident that is already owned.

Example: Datastore Capacity Alarm

An administrator selects the affected datastore and opens Monitor > Issues > Triggered Alarms.
The datastore capacity alarm is still in Warning status.
The administrator confirms that capacity cleanup or datastore expansion has been assigned to the storage team.
The administrator acknowledges the alarm to stop repeated configured notifications for the acknowledged alert.
The administrator verifies the acknowledgment timestamp and user identity.
The storage team continues monitoring until the capacity condition clears.

The alarm may remain in Warning status during this process. Acknowledgment records ownership and controls repeated alarm actions; it does not make the datastore capacity condition healthy.

Example: Persistent Host Connectivity Alert

A host connectivity alarm may remain in Alert status after review because the host is still unreachable. The operator can acknowledge the alert after opening an incident and assigning an investigation. The entry remains in Triggered Alarms until the monitored connectivity condition returns to normal or someone manually resets the alarm.

Reset to Green Is a Different Operation

Reset to Green is a manual operation separate from acknowledgment. It clears the active alarm indication and removes the alarm from the Triggered Alarms display. It does not prove that the original condition has been corrected.

Select the affected object and open Monitor > Issues > Triggered Alarms.
Select the triggered alarm.
Open the alarm action or context menu.
Choose Reset to Green when the operation is appropriate.
Verify that the alarm is no longer listed as a triggered alarm.
Separately validate the resource or service that caused the alarm.

A manual reset can remove the visible alarm even when the triggering issue still exists. Treat the reset as a change to alarm presentation and state handling, not as remediation.

Acknowledge Alarm vs. Reset to Green

Acknowledge — primary purpose: Record that the alert was seen and assigned to an operator or team.
Acknowledge — alarm actions: Suppresses further configured actions for the acknowledged alarm while it remains acknowledged.
Acknowledge — visibility: The alarm generally remains in the triggered list while its condition is active.
Acknowledge — resolution: Does not resolve the underlying condition or inherently return the alarm to Normal.
Acknowledge — caution: Use it after review, ownership assignment, and a remediation or investigation plan are established.
Reset to Green — primary purpose: Manually clear the active alarm indication.
Reset to Green — alarm actions: Changes the alarm handling state; do not assume that the underlying resource is healthy.
Reset to Green — visibility: Removes the active alarm from the Triggered Alarms display.
Reset to Green — resolution: Does not prove that the triggering condition has cleared.
Reset to Green — caution: Avoid it when the condition is not understood, evidence is still needed, or continued monitoring visibility is important.

Operational Decision Guidance

When acknowledgment is appropriate

The alert has been reviewed.
The affected resource and likely condition are understood well enough to begin response.
A responsible administrator or team has been identified.
Remediation is underway or has been completed but validation is still in progress.
Repeated notifications would create noise for an incident that is already being managed.

When to avoid Reset to Green

The triggering condition is not understood.
You still need the alarm visible while collecting evidence.
The responsible team has not accepted the incident.
The monitored resource has not been validated as healthy.
Resetting would make it harder for another operator to see an unresolved problem.

Document the cause, owner, remediation action, and validation result in your organization's incident process. This preserves operational context even after the alarm naturally returns to Normal or is manually reset.

Troubleshooting

The alarm remains in Warning or Alert after acknowledgment

The triggering condition is probably still present. Investigate and correct the monitored condition. Acknowledgment alone does not return an alarm to Normal.

The alarm disappeared after Reset to Green, but the problem may persist

The alarm was manually reset rather than naturally cleared by a healthy condition. Validate the underlying host, VM, datastore, network, service, or resource. Do not treat disappearance from the triggered list as confirmation of resolution.

The Acknowledge or Reset to Green action is unavailable

Confirm that the selected item is a currently triggered alarm and that you selected the affected object's Triggered Alarms view. If the action is still unavailable, review the vCenter permissions and role privileges assigned to your account.

The expected alarm cannot be found

The alarm may belong to a different inventory object, may be visible only at a parent or child scope, or may already have cleared. Check related parent and child objects, review current triggered alarms, and consult vCenter events or alarm history where available.

Exam-Relevant Notes

Acknowledgment records user ownership; it is not the same as resolving an alarm.
An acknowledged alarm can remain in Warning or Alert status.
Alarm actions can include notifications, scripts, and other automated responses.
Reset to Green is a separate manual operation that removes the alarm from the triggered display.
Normal generally results when the configured triggering condition clears.
The selected inventory scope affects which triggered alarms are visible.
Permissions may differ for viewing, acknowledging, and resetting alarms.