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

The Allegro Network Multimeter may be running as an IPFIX exporter. These settings allows configuration of reporting. When enabled, following settings are possible:

• IP address: Address of IPFIX collector
• Port: Corresponding port
• Protocol: TCP or UDP
• Update interval: Interval in seconds for sending a status update of flows
• UDP resend interval: Interval in seconds for resending IPFIX templates for UDP connections
• TCP reconnect timeout: When TCP connection could not be established, wait for this time period until next try to establish a connection.

Individual IPFIX messages can be enabled or disabled by toggling corresponding options. See the NetFlow/IPFIX interface documentation for details about the message types.

Time settings

The Allegro Network Multimeter can be configured to use a time synchronization service. NTP is supported for all variants of the Multimeter, PTP service may be used if management interface supports hardware time stamping. In case a GPS capable PTP grandmaster card is available, GPS time synchronization is available and the antenna cable delay in nanoseconds can be configured. To enable a time service, switch to the proper type in the dropdown box. The time service field will show whether the selected service is running or not. For NTP time retrieval you can specify and edit dedicated NTP servers. If you do not specify a NTP server, a set of predefined NTP servers will be taken automatically. For PTP time retrieval, the PTP grandmaster clock identity is shown. This is usually an EUI-64 address. The first and last set of octets of the identity represent the (EUI-48) MAC address of the grandmaster.

Following settings are possible for PTP and should match to the settings of the PTP grandmaster:

• Delay mechanism: Use end-to-end (E2E), peer-to-peer (P2P) or automatic delay measurement. In case automatic measurement is selected, E2E is used at the beginning and switched to P2P when a peer delay

request is received. Default is ‘Auto’.

• Network transport: Use UDPv4, UDPv6 or Layer 2 as network transport. Default is ‘UDPv4’.

• Domain number: The domain number of the grandmaster. This is used to define logical groups of synchronized clocks.

The GPS time retrieval option is available if a GPS capable PTP grandmaster card is installed in the Multimeter.

If no time synchronization mechanism is selected the date and time of the device can be configured manually by entering a properly formatted date and time description.

Below the time synchronization settings the time zone used by the device can be configured. The drop-down list provides a list of cities grouped by world regions to select the appropriate time zone from.

To make changes take effect, click on the Save settings button on the bottom of the page. To reload the stored settings, click on Reload 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==