Settings

The Settings sub-menu allows for configuring several system parameters and for updating the system. The Allegro Network Multimeter is designed to work out-of-the-box in most installation scenarios. Therefore there are no mandatory options that must be configured before using the system.

The following setting sections are available:

Global settings

The Global settings section contains parameters for adjusting the behavior of the system.

The settings are split among multiple tabs, described as follows.

Generic Settings

Packet processing mode

This section allows for configuring the main packet processing mode:

• Bridge mode: In bridge mode, all received packets will be transmitted again on the corresponding mutual port so that the device can be placed in-line between any network component. The device will be transparent and will not modify the traffic in any way. The additional latency will be typically around or less than 1 millisecond.

• Sink mode: In sink mode, packets are only received and not forwarded. This operation mode allows for installation at a mirror port of a switch or when using a network tap to access the network traffic.

The packet processing mode can be changed during run-time.

Webshark support

The Allegro Network Multimeter allows having a preview of the first Megabyte of packets directly in the browser, called Webshark. To support this, the system needs a small amount of system memory to process the packets.

This amount of memory (~100MB) will be reserved by the system and is not available for the In-Memory database used to store metadata, thus the history of stored metadata is a bit shorter.

If this is not desired, it is possible to disable the Webshark support.

Changing this value requires a restart of the processing.

Limit module processing

This setting allows to configure which modules are active. With this setting, the performance of the Allegro Network Multimeter can be drastically improved and allows a higher throughput if you don’t need some analysis modules.

Following modes are possible:

• Only capturing: Only interface statistics and the capture module is provided. The capture filters are support except layer 7 protocol recognition.

• Up to layer 2: Additionally all layer 2 related modules are active such as MAC, MAC protocols, ARP and Burst Analysis.

• Up to layer 3: Additionally all layer 3 related modules are active such as IP and DHCP statistics.

• Up to layer 4: Additionally all layer 4 related modules are active such as TCP and Layer 4 server ports.

• Unlimited: All modules are active.

When switching to another mode you have to restart the processing in order to activate the new settings.

Graph detail settings

It is possible to modify the detail level of all graphs in the interface.

This settings allow to get a more detailed view (with higher time resolution) or to reduce the detail level so that more data can be stored on the device.

Changing the default values have an impact on the performance and memory usage. Changing a slider to the left increases detail level of graphs, but also increases the memory usage and decreases the performance.

• Best graph resolution: This option configures how detailed the graph information are shown in the best case (the latest information).

The default value is one second which means that a graph sample point represents a second of packet time. You can change the resolution up to 1 millisecond which gives a detailed sub-second representation of the traffic. You can also decide to decrease the resolution which enables the Multimeter to store more data for a longer period of time.

• Reduce graph resolution of old data by up to: The resolution of older graph data is automatically reduced to save memory and to allow a longer view into the traffic history. This option allows to change this behavior.

With a reduction factor of 1/1 no reduction is done at all which means the selected graph resolution is available for the complete time. This of course reduces the time period to see historical data. You can also choose to increase the reduction factor to be able to store more data for a longer time. The time printed in parentheses represents the worst-case graph resolution based on the chosen resolution and reduction factor. Note: Regardless of these settings, the graph values are always converted to represent a value per second (when applicable). For example, the packets per second for IP addresses will always be a value literally per second even if the resolution is larger or smaller than one second. The shown value is scaled to match this view. Especially with sub-second resolution this might be misleading. For instance, if there is a network element sending one packet per second and the resolution is set to 100 millisecond, the value might be shown as 10 packets per second as each sample point is scaled to represent an value per second. For a detailed investigation it is recommended to select a specific time interval since the total packet counters shown in all statistics are unscaled and represent the actual values.

Performance implications: The performance degradation and memory usage depends on the actual network traffic and is not exactly predictable. Here are some examples for reference on a Multimeter 1000 series with different configuration values (under ideal test conditions):

• 1 second resolution, 1/1 reduction factor: 90% of default performance
• 100 millisecond resolution, 1/1 reduction factor: 50% of default performance,
• 10 millisecond resolution, 1/1 reduction factor: 15% of default performance
• 1 millisecond resolution, 1/1 reduction factor: 10% of default performance

IPFIX settings Time settings Email notification Expert settings

Packet length accounting VLAN handling Tunnel view mode Database mode settings Network performance Processing performance Packet ring buffer timeouts Data retention timeout L3 tunnel mode

Module settings

Capture traffic IP statistics Interface and MAC throughput

User defined names

Wireless management interface LAN management interface Secondary management interface Host name LLDP

Administration

SSL certificate

Filter

IP filters

Remote access and export

Statistics Export

SSH Port Forwarding

Preparing the SSH server Create a user Allow SSH access via public key Option 1: No proxy Option 2: With HTTPS proxy Configuration of the multimeter

Allegro Remote Service SNMP

User Management Roles LDAP users

==Firmware update== == License upload==