Please follow these steps to start monitoring your network traffic with sFlowTrend-Pro. It will also be useful to have the documentation available for your network switches.
Ensure that you have some switches that support sFlow. sFlowTrend-Pro can only monitor switches using sFlow.
Select the sFlowTrend-Pro → menu item and select the Advanced tab. Note the sFlow collector address and UDP port that sFlowTrend-Pro is using to receive sFlow. If your host has multiple IP addresses, they will be accessible through the sFlow collector address selector. Select the most appropriate IP address for sFlowTrend-Pro to use to receive sFlow.
-
Make sure that any host based firewalls, or external firewalls between the host running sFlowTrend-Pro and the switches being monitored allow:
- UDP traffic from the switches being monitored to the sFlow port on the host running sFlowTrend-Pro.
- UDP traffic to and from the host running sFlowTrend-Pro to the SNMP port (port 161) on the switches being monitored.
Select the → menu item and select the SNMP tab. Enter the default community name for your network. In addition to this global setting, the community can also be configured per switch (see Section 6.1, “Configuring switches in sFlowTrend-Pro”). Note that the community name must be the write community if your switches are to be configured using SNMP (see below). If the switches are configured manually, then the read community can be used.
-
Next, sFlow should be enabled on the switches you wish to monitor. How this is done depends on the make and model of each switch. Some switches support sFlow configuration through SNMP, while others require that it is manually configured through the configuration interface for the switch (normally the web interface or command line interface (CLI)). In some cases, the switch can be configured either way. SNMP configuration is normally the easiest. Consult the switch vendor's documentation to determine how sFlow can be configured, and for any specific instructions. See Section A.1, “Configuring switches to send sFlow” for additional information on configuring switches.
- SNMP configured sFlow
- If a switch supports SNMP configuration of sFlow, then sFlowTrend-Pro can do most of the configuration work. To do this, select the → menu item. Click the button, and enter the IP address of the switch you wish to configure. The community name for the switch can also be changed from the default here. Select on both dialogs to apply your changes. See Section 6.1.1, “Adding a switch that is to be configured using SNMP” for more information on configuring switches with SNMP.
- Manually configured sFlow
-
To manually configure a switch to send sFlow, consult the switch documentation to determine the specific steps required. Normally, this is done through the web interface or the command line interface on the switch. Connect to the switch (say using a web browser, ssh or telnet). Follow the instructions for the switch to configure it to send sFlow to the IP address and UDP port that sFlowTrend-Pro is using to receive sFlow. You will also need to enable sFlow on one or more interfaces on the switch and set a sampling rate.
As soon as sFlow reaches sFlowTrend-Pro, the switch will automatically be added to sFlowTrend-Pro. Even though the switch is not configured through SNMP, configuring sFlowTrend-Pro with the SNMP read community for the switch will allow information about the switch to be displayed in a more useful way. For example the interfaces can be displayed by name, rather than number. See Section 6.1, “Configuring switches in sFlowTrend-Pro” for more information on this topic.
When sFlowTrend-Pro starts to receive sFlow, the green 'LED' at the bottom right of the window should start flashing. This flashes for each sFlow sample received, so the more sFlow being received, the faster it will flash. Also, on the dashboard, you can check the incoming sample rate in the Status section.
Now that your switches are configured to send sFlow, they should be visible within sFlowTrend-Pro. Go to the Charts tab, and then use the Switch selector to view the traffic information for a specific switch. The default view shows top sources across all interfaces on the switch. You can change the chart displayed using the Chart selector, and view data for a specific interface using the Interface selector. See Chapter 3, Charts for more information on charts.
To quickly find the interfaces on a switch that are busiest, select the Interfaces tab. This will show a table of all the interfaces on the selected switch. By clicking on the column headings, you can sort by Utilization, Unicasts per second, etc. Once you have found an interface of interest, click the chart
button, at the left-hand end of each row, to go
directly to the charts for that interface. See
Chapter 4, Switch interface statistics
for more information on this tab.