Cisco N5010P-N2K-BE, Software Configuration Manual

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5-4
Cisco Nexus 5000 Series Switch CLI Software Configuration Guide
OL-16597-01
Chapter 5 Configuring Ethernet Interfaces
Information About Ethernet Interfaces
In these cases, the UDLD aggressive mode disables one of the ports on the link, which prevents traffic
from being discarded.
About Interface Speed
A Cisco Nexus 5000 Series switch has a number of fixed 10-Gigabit ports, each equipped with SFP+
interface adapters. The Cisco Nexus 5010 switch has 20 fixed ports, the first 8 of which are switchable
1-Gigabit and 10-Gigabit ports. The Cisco Nexus 5020 switch has 40 fixed ports, the first 16 of which
are switchable 1-Gigabit and 10-Gigabit ports.
About the Cisco Discovery Protocol
CDP is a device discovery protocol that runs over Layer 2 (the data link layer) on all Cisco-manufactured
devices (routers, bridges, access servers, and switches) and allows network management applications to
discover Cisco devices that are neighbors of already known devices. With CDP, network management
applications can learn the device type and the Simple Network Management Protocol (SNMP) agent
address of neighboring devices running lower-layer, transparent protocols. This feature enables
applications to send SNMP queries to neighboring devices.
CDP runs on all media that support Subnetwork Access Protocol (SNAP). Because CDP runs over the
data-link layer only, two systems that support different network-layer protocols can learn about each
other.
Each CDP-configured device sends periodic messages to a multicast address, advertising at least one
address at which it can receive SNMP messages. The advertisements also contain time-to-live, or
holdtime information, which is the length of time a receiving device holds CDP information before
discarding it. Each device also listens to the messages sent by other devices to learn about neighboring
devices.
The switch supports both CDP Version 1 and Version 2.
Default CDP Configuration
Table 5-2 shows the default CDP configuration.
About the Debounce Timer Parameters
The port debounce time is the amount of time that an interface waits to notify the supervisor of a link
going down. During this time, the interface waits to see if the link comes back up. The wait period is a
time when traffic is stopped.
You can enable the debounce timer for each interface and specify the delay time in milliseconds.
Table 5-2 Default CDP Configuration
Feature Default Setting
CDP interface state Enabled
CDP timer (packet update frequency) 60 seconds
CDP holdtime (before discarding) 180 seconds
CDP Version-2 advertisements Enabled