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Cisco Intrusion Prevention System Sensor CLI Configuration Guide for IPS 7.2
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Chapter4 Configuring Interfaces
Configuring CDP Mode
User the cdp-mode command in service interface mode to have the sensor either forward or drop CDP
packets.
The following option applies:
•
cdp-mode {forward-cdp-packets | drop-cdp-packets}—Configures the sensor to either forward
CDP packets or drop CDP packets. The default is drop-cdp-packets.
Enabling CDP Mode
To configure CDP mode, follow these steps:
Step 1
Log in to the CLI using an account with administrator privileges.
Step 2
Enter interface submode.
sensor# configure terminal
sensor(config)# service interface
Step 3
Enable CDP mode.
sensor(config-int)# cdp-mode forward-cdp-packets
Step 4
Verify the settings.
sensor(config-int)# show settings
-----------------------------------------------
bypass-mode: auto <defaulted>
interface-notifications
-----------------------------------------------
missed-percentage-threshold: 0 percent <defaulted>
notification-interval: 30 seconds <defaulted>
idle-interface-delay: 30 seconds <defaulted>
-----------------------------------------------
cdp-mode: forward-cdp-packets default: drop-cdp-packets
sensor(config-int)#
Displaying Interface Statistics
Note
The show interface command output for the IPS 4510 and IPS 4520 does no t include the total undersize
packets or total transmit FIFO overruns.
Note
When the IPS 4510 and IPS 4520 a re in bypass mode, VLAN statistics in the show interface and packet
display/capture command output do not show any packets.
The jumbo packet count in the show interface command output from the lines
Total Jumbo Packets
Received
and
Total Jumbo Packets Transmitted
for ASA IPS modules may be larger than expected
due to some packets that were almost jumbo size on the wire being counted as jumbo size by the IPS.
This miscount is a result of header bytes added to the packet by the ASA before the packet is transmitted
to the IPS. For IPv4, 58 bytes of header data are added. For IPv6, 78 bytes of header data are ad ded. The
ASA removes the added IPS header before the packet leaves the ASA.