An administrator is configuring the severity level on the vManage NMS for events that indicate that an action must be taken immediately. Which severity level must be configured?

'Warning' indicates a potential problem that is not immediately service-affecting but should be monitored for future issues.

'Error' signifies a problem that prevents a system or operation from functioning correctly but may not require the same level of urgent, immediate intervention as a critical condition.

The 'critical' severity level in vManage NMS is used for conditions that indicate severe system issues requiring immediate attention and action to prevent further degradation or service disruption. This level commonly represents the threshold for events demanding prompt administrative intervention to maintain system stability.

'Alert' typically signifies an even higher severity condition that requires immediate action for widespread or system-wide failure, often indicating a more catastrophic event than 'critical'.