Passive monitors are the WhatsUp Gold feature responsible for listening for device events. As active monitors actively query or poll devices for data, passive monitors passively listen for device events. Because passive monitors do not poll devices, they use less network bandwidth than active monitors.
Passive monitors are useful because they gather information that goes beyond simple Up or Down service and device states by listening for a variety of events. For example, if you want to know when someone with improper credentials tries to access one of your SNMP-enabled devices, you can assign the default Authentication Failure passive monitor. The monitor listens for an authentication failure trap on the SNMP device, and logs these events to the SNMP Trap Log. If you assign an action to the monitor, every time the authentication failure trap is received, you are notified as soon as it happens.
Although passive monitors are useful, you should not rely on them solely to monitor a device or servicepassive monitors should be used in conjunction with active monitors. When used together, active and passive monitors make up a powerful and crucial component of 360-degree network management.
Passive monitor types are specific configurations of SNMP traps, Windows Log Events, and Syslog Events.
After the monitor types are configured, you can associate them to devices on the Passive Monitors section of Device Properties dialog. For more information, see Assigning passive monitors.
Passive Monitors are configured and stored in the Passive Monitor Library. Using the Passive Monitor Library, you can:
For more information, see Configuring passive monitors.
Creating a successful passive monitor requires that you take several steps:
Important: Before you attempt to create a passive monitor, you should know the specific traps (and coinciding MIBs) for which you want WhatsUp Gold to listenthis makes the process much easier.
Additionally, after you create a passive monitor, you can configure alerts to notify you when a particular trap is received. For more information, see Actions overview.