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Cisco Broadband Cable Command Reference Guide
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Chapter 2 Cisco CMTS Configuration Commands
cable source-verify leasequery-filter upstream
Note
The
cable source-verify leasequery-filter upstream
command enables DHCP lease query filtering on
all upstreams on a cable interface, but the actual filtering does not begin until the
cable source-verify
dhcp
command and the
no cable arp
command are configured on the upstream’s associated downstream
interface. You can configure these commands on either the downstream’s main interface, or on a
subinterface for the downstream. If these commands are configured on a subinterface, however, the lease
query filtering occurs only for cable modems using that subinterface.
Note
If using cable interface bundling, configure the
cable source-verify leasequery-filter upstream
command on all master and slave interfaces.
Tip
Use the
cable source-verify leasequery-filter downstream
command to filter DHCP LEASEQUERY
requests in the downstream direction.
Examples
The following example shows how to configure the Cisco CMTS router so that it allows a maximum of
five DHCP lease query requests per SID over each two-second interval on all upstreams on a particular
cable interface. This example also shows the configuration of
cable source-verify dhcp
and
no cable
arp
commands on the cable interface, which are required to use this feature.
Router#
configure terminal
Router(config)#
interface cable 6/0
Router(config-if)#
cable source-verify dhcp
Router(config-if)#
cable source-verify leasequery-filter upstream 5 2
Router(config-if)#
no cable arp
Router(config-if)#
Related Commands
Command
Description
cable arp
Activates the cable Address Resolution Protocol (ARP).
cable arp filter
Controls the number of ARP requests and replies that can be forwarded over
a cable interface.
cable source-verify
Enables verification of IP addresses for cable modems (CMs) and CPE
devices on the upstream.
cable source-verify
leasequery-filter
downstream
Controls the number of DHCP lease query messages that are sent for
unknown IP addresses on all cable downstream interfaces on the
Cisco CMTS router.
show cable
leasequery-filter
Displays the number of DHCP lease query messages that have been filtered
for all cable modems or for a particular cable interface.