C-30

Cisco Intrusion Prevention System Sensor CLI Configuration Guide for IPS 7.2
OL-29168-01
AppendixC Troubleshooting
Troubleshooting the Appliance
Physical Connectivity, SPAN, or VACL Port Issue

If the sensor is not connected properly, you do not receive any alerts.

To make sure the sensor is connected properly, follow these steps:

Step 1
Log in to the CLI.
Step 2

Make sure the interfaces are up and that the packet count is increasing.

sensor# show interfaces
Interface Statistics
Total Packets Received = 0
Total Bytes Received = 0
Missed Packet Percentage = 0
Current Bypass Mode = Auto_off
MAC statistics from interface GigabitEthernet0/1
Media Type = backplane
Missed Packet Percentage = 0
Inline Mode = Unpaired
Pair Status = N/A
Link Status = Up
Link Speed = Auto_1000
Link Duplex = Auto_Full
Total Packets Received = 0
Total Bytes Received = 0
Total Multicast Packets Received = 0
Total Broadcast Packets Received = 0
Total Jumbo Packets Received = 0
Total Undersize Packets Received = 0
Total Receive Errors = 0
Total Receive FIFO Overruns = 0
Total Packets Transmitted = 0
Total Bytes Transmitted = 0
Total Multicast Packets Transmitted = 0
Total Broadcast Packets Transmitted = 0
Total Jumbo Packets Transmitted = 0
Total Undersize Packets Transmitted = 0
Total Transmit Errors = 0
Total Transmit FIFO Overruns = 0
MAC statistics from interface GigabitEthernet0/0
Media Type = TX
Link Status = Up
Link Speed = Auto_100
Link Duplex = Auto_Full
Total Packets Received = 1830137
Total Bytes Received = 131624465
Total Multicast Packets Received = 20
Total Receive Errors = 0
Total Receive FIFO Overruns = 0
Total Packets Transmitted = 220052
Total Bytes Transmitted = 103796666
Total Transmit Errors = 0
Total Transmit FIFO Overruns = 0
sensor#
Step 3

If the Link Status is down, make sure the sensing port is connected properly:

•

Make sure the sensing port is connected properly on the appliance.

•

Make sure the sensing port is connected to the correct SPAN or VACL capture port on IDSM2.