Juniper Networks IDP 800, IDP250, IDP8200 Connecting Forwarding Interfaces, Verifying Traffic Flow

IDP 75, 250, 800, and 8200 Installation Guide

In proxy-ARP or router mode, if you are using multiple subnets in your protected network, you must configure static routes on the IDP sensor to these subnets. Without static routes, incoming traffic to those subnets can be lost. Alternatively, you can create a static route from the IDP sensor to an internal gateway that contains inbound routes to the protected subnets. (This does not apply to the IDP 8200 sensor.)

Connecting Forwarding Interfaces

Connect the ports on the sensor to either the protected network or the external network. See “Planning an Installation” on page 1 for the configuration you chose to implement. See “NIC Bypass and Cable Choices” on page 12 for information on using NIC bypass with transparent mode.

Inline transparent mode makes use of pairs of interfaces. On most sensors, the pairs are horizontal port pairs 0-1and 2-3 on each NIC. Traffic in inline transparent mode only flows between paired interfaces. You cannot have traffic flow from port 0 to port 2, for example, in inline transparent mode.

Other modes, such as router and proxy-ARP mode, do support non-paired interfaces.

Verifying Traffic Flow

To verify that traffic is flowing through your sensor:

1.Make sure your sensor is connected to a live traffic feed.

2.Log onto the sensor as root using the console serial port, or open an SSH connection to the management port.

3.Type sctop and press Enter.

4.Type s to see status information.

5.Examine the following information on the screen:

Protocol Packets		Flows	Sessions	Peak	Peak Time
Other	2	0	0	1	08/09/2006 03:08:07
ICMP	3	0	0	0	08/08/2006 18:03:51
UDP	3386	3	1	7	08/08/2006 19:31:01
TCP	151164	12	6	9	08/09/2006 07:01:36

6. Make sure the UDP or TCP values are changing.

Connecting the High Availability Port

After you have set up both machines in the HA cluster, connect their HA ports to each other using a crossover cable.

28„ Connecting Forwarding Interfaces