PRTG Manual: Packet Sniffer (Custom) Sensor
The Packet Sniffer (Custom) sensor monitors the headers of data packets that pass a local network card using a built-in packet sniffer. With this sensor, you can define your own channel definitions to divide traffic into different channels.
The sensor analyzes only header traffic.
This sensor does not have any predefined channels.
For a detailed list and descriptions of the channels that this sensor can show, see section Channel List.
- Dutch: Packet Sniffer (Aangepast)
- French: Reniflage de paquets personnalisé
- German: Packet Sniffer (Benutzerdef.)
- Japanese: パケットスニファー(カスタム)
- Portuguese: Sniffer de pacotes (customizado)
- Russian: Анализатор пакетов (нестандартный)
- Simplified Chinese: 数据包嗅探程序 (自定义)
- Spanish: Analizador de paquetes (personalizado)
- This sensor has a very high performance impact. Use it with care. We recommend that you use no more than 50 sensors of this sensor type on each probe.
- By default, this sensor works only on a probe device.
- This sensor supports the IPv6 protocol.
- This sensor does not officially support more than 50 channels. Depending on the data used with this sensor, you might exceed the maximum number of supported channels. In this case, PRTG tries to display all channels. Be aware, however, that you experience limited usability and performance.
By default, you can only monitor traffic passing the probe system where the probe device with the sensor is set up. To monitor other traffic in your network, you can configure a monitoring port (if available) that the switch sends a copy of all traffic to. You can then physically connect this port to a network card of the probe system (either local probe or remote probe system). This way, PRTG can analyze the complete traffic that passes through the switch. This feature of your hardware might be called Switched Port Analyzer (SPAN), port mirroring, or port monitoring.
You cannot add this sensor to the hosted probe of a PRTG Hosted Monitor instance. If you want to use this sensor, add it to a remote probe device.
The Add Sensor dialog appears when you manually add a new sensor to a device. It only shows the settings that are required to create the sensor. You can change nearly all settings on the sensor's Settings tab after creation.
Click the Settings tab of a sensor to change its settings.
Setting |
Description |
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Sensor Name |
Enter a name to identify the sensor. |
Parent Tags |
Shows tags that the sensor inherits from its parent device, parent group, and parent probe.
|
Tags |
Enter one or more tags. Confirm each tag with the Spacebar key, a comma, or the Enter key. You can use tags to group objects and use tag-filtered views later on. Tags are not case-sensitive. Tags are automatically inherited.
The sensor has the following default tags that are automatically predefined in the sensor's settings when you add the sensor:
|
Priority |
Select a priority for the sensor. This setting determines the position of the sensor in lists. The highest priority is at the top of a list. Choose from the lowest priority ( |
For detailed information on filters, see section Filter Rules.
Setting |
Description |
---|---|
Include Filter |
Define if you want to filter any traffic. If you leave this field empty, the sensor includes all traffic. To include specific traffic only, define filters using a special syntax. |
Exclude Filter |
First, the sensor considers the filters in Include Filter. From this subset, you can explicitly exclude traffic, using the same syntax. |
Channel Definition |
Enter a channel definition to divide the traffic into different channels. Enter each definition in one line. The sensor accounts all traffic that you do not define a channel for to the default channel Other.
|
Network Adapters |
Select the network adapters that this sensor monitors. You see a list of all adapters that are available on the probe system. To select an adapter, enable the check box in front of the respective name.
|
Stream Data Handling |
Define what PRTG does with the stream and packet data:
|
Setting |
Description |
---|---|
Primary Channel |
Select a channel from the list to define it as the primary channel. In the device tree, the last value of the primary channel is always displayed below the sensor's name. The available options depend on what channels are available for this sensor.
|
Graph Type |
Define how different channels are shown for this sensor:
|
Stack Unit |
This setting is only visible if you enable Stack channels on top of each other as Graph Type. Select a unit from the list. All channels with this unit are stacked on top of each other. By default, you cannot exclude single channels from stacking if they use the selected unit. However, there is an advanced procedure to do so. |
Setting |
Description |
---|---|
Primary Toplist |
Define which Toplist is the primary Toplist of the sensor:
|
By default, all of the following settings are inherited from objects that are higher in the hierarchy. We recommend that you change them centrally in the root group settings if necessary. To change a setting for this object only, click under the corresponding setting name to disable the inheritance and to display its options.
For more information, see section Inheritance of Settings.
Click to interrupt the inheritance.
Setting |
Description |
---|---|
Scanning Interval |
Select a scanning interval from the dropdown list. The scanning interval determines the amount of time that the sensor waits between two scans. Choose from:
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If a Sensor Query Fails |
Select the number of scanning intervals that the sensor has time to reach and to check a device again if a sensor query fails. Depending on the option that you select, the sensor can try to reach and to check a device again several times before the sensor shows the Down status. This can avoid false alarms if the monitored device only has temporary issues. For previous scanning intervals with failed requests, the sensor shows the Warning status. Choose from:
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Schedules, Dependencies, and Maintenance Window
You cannot interrupt the inheritance for schedules, dependencies, and maintenance windows. The corresponding settings from the parent objects are always active. However, you can define additional schedules, dependencies, and maintenance windows. They are active at the same time as the parent objects' settings.
Setting |
Description |
---|---|
Schedule |
Select a schedule from the list. You can use schedules to monitor during a certain time span (days or hours) every week. Choose from:
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Maintenance Window |
Select if you want to set up a one-time maintenance window. During a maintenance window, monitoring stops for the selected object and all child objects. They show the Paused status instead. Choose between:
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Maintenance Begins |
This setting is only visible if you enable Set up a one-time maintenance window above. Use the date time picker to enter the start date and time of the one-time maintenance window. |
Maintenance Ends |
This setting is only visible if you enable Set up a one-time maintenance window above. Use the date time picker to enter the end date and time of the one-time maintenance window. |
Dependency Type |
Select a dependency type. You can use dependencies to pause monitoring for an object depending on the status of a different object. You can choose from:
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Dependency |
This setting is only visible if you enable Select a sensor above. Click |
Dependency Delay (Sec.) |
This setting is only visible if you select Select a sensor above. Define a time span in seconds for the dependency delay. After the master sensor for this dependency returns to the Up status, PRTG additionally delays the monitoring of the dependent objects by the time span you define. This can prevent false alarms, for example, after a server restart or to give systems more time for all services to start. Enter an integer value.
|
Click to interrupt the inheritance.
Setting |
Description |
---|---|
User Group Access |
Define the user groups that have access to the sensor. You see a table with user groups and group access rights. The table contains all user groups in your setup. For each user group, you can choose from the following group access rights:
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Click to interrupt the inheritance.
Setting |
Description |
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Channel Unit Types |
For each type of channel, select the unit in which PRTG displays the data. If you define this setting on probe, group, or device level, you can inherit these settings to all sensors underneath. You can set units for the following channel types (if available):
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For all Flow (NetFlow, jFlow, sFlow, IPFIX) and Packet Sniffer sensors, Toplists are available on the sensor's Overview tab. Using Toplists, you can review traffic data for small time periods in great detail.
For more information, see section Toplists.
The following filter rules apply to all Flow (NetFlow, jFlow, sFlow, IPFIX) and Packet Sniffer sensors.
For more information, see section Filter Rules for Flow, IPFIX, and Packet Sniffer Sensors.
Field |
Possible Filter Values |
---|---|
IP |
IP address or DNS name |
Port |
Any number |
SourceIP |
IP address or DNS name |
SourcePort |
Any number |
DestinationIP |
IP address or DNS name |
DestinationPort |
Any number |
Protocol |
Transmission Control Protocol (TCP), User Datagram Protocol (UDP), Internet Control Message Protocol (ICMP), Open Shortest Path First (OSPF), any number |
ToS |
Type of Service (ToS): any number |
DSCP |
Differentiated Services Code Point (DSCP): any number |
The following filter rules apply to Packet Sniffer sensors only.
Field |
Possible Filter Values |
---|---|
MAC |
Physical address |
SourceMAC |
Physical address |
DestinationMAC |
Physical address |
EtherType |
IPV4, ARP, RARP, APPLE, AARP, IPV6, IPXold, IPX, any number |
VlanPCP |
IEEE 802.1Q VLAN Priority Code Point |
VlanID |
IEEE 802.1Q VLAN Identifier |
TrafficClass |
IPv6 Traffic Class: corresponds to TOS used with IPv4 |
FlowLabel |
IPv6 Flow Label |
Which channels the sensor actually shows might depend on the monitored device, the available components, and the sensor setup.
Channel |
Description |
---|---|
[Custom] |
The traffic by type according to the channel definition |
Downtime |
In the channel table on the Overview tab, this channel never shows any values. PRTG uses this channel in graphs and reports to show the amount of time in which the sensor was in the Down status in percent. |
Other |
All traffic for which no channel is defined in bytes per second |
Total |
The total traffic in bytes per second
|
Knowledge Base
What security features does PRTG include?
Where is the volume line in graphs?
For more information about sensor settings, see the following sections: