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cdp advertise-v2 through show cdp traffic
- cdp advertise-v2
- cdp enable
- cdp holdtime
- cdp log mismatch duplex
- cdp run
- cdp source-interface
- cdp timer
- cdp tlv
- clear cdp counters
- clear cdp table
- show cdp
- show cdp entry
- show cdp interface
- show cdp neighbors
- show cdp tlv
- show cdp traffic
cdp advertise-v2
To enable Cisco Discovery Protocol Version 2 (CDPv2) advertising functionality on a device, use the cdp advertise-v2 command in global configuration mode. To disable advertising CDPv2 functionality, use the no form of the command.
Command History
Release
Modification
12.0(3)T
This command was introduced.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support in a specific 12.2SX release of this train depends on your feature set, platform, and platform hardware.
Usage Guidelines
CDP Version 2 has three additional type-length values (TLVs): VTP Management Domain Name, Native VLAN, and full/half-Duplex.
Examples
In the following example, CDP Version 2 advertisements are disabled on the router:
Router# show cdp Global CDP information: Sending CDP packets every 60 seconds Sending a holdtime value of 180 seconds Sending CDPv2 advertisements is enabled Router# configure terminal Enter configuration commands, one per line. End with CNTL/Z. Router(config)# no cdp advertise-v2 Router(config)# end Router# show cdp Global CDP information: Sending CDP packets every 60 seconds Sending a holdtime value of 180 seconds Sending CDPv2 advertisements is not enabled Router#cdp enable
To enable Cisco Discovery Protocol (CDP) on an interface, use the cdp enable command in interface configuration mode. To disable CDP on an interface, use the noform of this command.
Command Default
This command is enabled at the global configuration level and is supported on all interfaces.
Command History
Release
Modification
10.3
This command was introduced.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support in a specific 12.2SX release of this train depends on your feature set, platform, and platform hardware.
15.1(2)SNG
This command was implemented on Cisco ASR 901 Series Aggregation Services Routers.
Usage Guidelines
CDP is enabled by default at the global level and on each supported interface in order to send or receive CDP information. However, some interfaces, such as ATM interfaces, do not support CDP.
NoteThe cdp enable, cdp timer, and cdp run commands affect the operation of the IP on demand routing feature (that is, the router odr global configuration command). For more information on the router odr command, see the “On-Demand Routing Commands” chapter in the Cisco IOS IP Command Reference , Volume 2 of 3: Routing Protocols document.
Examples
In the following example, CDP is disabled on Ethernet interface 0 only:
Router# show cdp Global CDP information: Sending CDP packets every 60 seconds Sending a holdtime value of 180 seconds Sending CDPv2 advertisements is enabled Router# configure terminal Router(config)# interface ethernet 0 Router(config-if)# no cdp enablecdp holdtime
To specify the amount of time the receiving device should hold a Cisco Discovery Protocol (CDP) packet from the router before discarding it, use the cdp holdtime command in global configuration mode. To revert to the default setting, use the noform of this command.
Command History
Release
Modification
10.3
This command was introduced.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support in a specific 12.2SX release of this train depends on your feature set, platform, and platform hardware.
Usage Guidelines
CDP packets are sent with a time to live, or hold time, value. The receiving device will discard the CDP information in the CDP packet after the hold time has elapsed.
You can set the hold time lower than the default setting of 180 seconds if you want the receiving devices to update their CDP information more rapidly.
The CDP hold time must be set to a higher number of seconds than the time between CDP transmissions, which is set using the cdp timer command.
cdp log mismatch duplex
To display the log of duplex mismatches generated by the Cisco Discovery Protocol on Ethernet interfaces, use the cdp log mismatch duplex command in global configuration mode or in interface configuration mode. To disable the display of duplex messages, use the no form of this command.
Usage Guidelines
Duplex mismatches can occur only on Ethernet interfaces.
When you enter the cdp log mismatch duplex command in global configuration mode, duplex mismatches are displayed for all Ethernet interfaces on the device. If the command is disabled in global configuration mode, the command cannot be configured in interface configuration mode. When you enter the cdp log mismatch duplex command in interface configuration mode, only duplex mismatches for the specified Ethernet interface are displayed.
To enable reporting of duplex mismatches, issue the cdp log mismatch duplex command in global configuration mode. If the command was previously disabled under a specified interface, issue the command in interface configuration mode for that interface.
To disable reporting of duplex mismatches globally, issue the no cdp log mismatch duplex command in global configuration mode. To disable reporting duplex mismatches for a specified Ethernet interface, use the no cdp log mismatch duplex command in interface configuration mode.
Examples
The following example shows how to enable the display of duplex messages from all Ethernet interfaces on a router:
Router(config)# cdp log mismatch duplexThe following example shows how to enable the display of duplex messages that may be generated from only Ethernet interface 2/1:
Router(config)# interface ethernet2/1 Router(config-if)# cdp log mismatch duplexThe following is sample output from the show running-config command. The bold text in the output shows that the cdp log mismatch duplexcommand is disabled globally.
Router# show running-config version 12.2 hostname Router ! interface Ethernet2/0 no ip address duplex half interface Ethernet2/1 no ip address duplex half ! no cdp log mismatch duplex ! line con 0 line aux 0The following is sample output from the show running-config command. The bold text in the output shows that the cdp log mismatch duplex command is disabled under a specific interface.
Router# show running-config version 12.2 hostname Router ! interface Ethernet2/0 no ip address duplex half no cdp log mismatch duplex interface Ethernet2/1 no ip address duplex half !! line con 0 line aux 0 line vty 0 4cdp run
To enable Cisco Discovery Protocol, use the cdp runcommand in global configuration mode. To disable Cisco Discovery Protocol, use the noform of this command.
Command Default
This command is enabled on all the platforms except for the Cisco 10000 Series Edge Services Router platform.
Command History
Release
Modification
10.3
This command was introduced.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support in a specific 12.2SX release of this train depends on your feature set, platform, and platform hardware.
15.1(2)SNG
This command was implemented on the Cisco ASR 901 Series Aggregation Services Routers.
Usage Guidelines
Cisco Discovery Protocol is enabled by default on all platforms except the Cisco 10000 Series Edge Services Router, which means Cisco IOS software receives Cisco Discovery Protocol information. Cisco Discovery Protocol also is enabled on supported interfaces by default. To disable Cisco Discovery Protocol on an interface, use the no cdp enable command in interface configuration mode.
The show running-config command lists no cdp run when Cisco Discovery Protocol is disabled globally, which is not the default behavior. As a result of changes made for the Cisco 10000 platform, the show running-config command will list the cdp run command when Cisco Discovery Protocol is enabled globally.
NoteBecause on-demand routing (ODR) uses Cisco Discovery Protocol, the cdp enable, cdp timer, and cdp run commands affect the operation of the router odr global configuration command. For more information about the router odr command, see the Cisco IOS IP Command Reference, Volume 2 of 3: Routing Protocols document.
Examples
In the following example, Cisco Discovery Protocol is disabled globally, and then the user attempts to enable it on the Ethernet interface 0:
Router(config)# no cdp run Router(config)# end Router# show cdp % CDP is not enabled Router# configure terminal Enter configuration commands, one per line. End with CNTL/Z. Router(config)# interface ethernet0 Router(config-if)# cdp enable % Cannot enable CDP on this interface, since CDP is not running Router(config-if)#Related Commands
Command
Description
cdp enable
Enables Cisco Discovery Protocol on a supported interface.
cdp holdtime
Specifies the amount of time that a receiving device should hold a Cisco Discovery Protocol packet before discarding it.
cdp timer
Specifies how often the Cisco IOS software sends Cisco Discovery Protocol updates.
router odr
Enables ODR on the hub router.
cdp source-interface
To configure the Cisco Discovery Protocol source interface, use the cdp source-interface command in global configuration mode.
Usage Guidelines
Use of this command ensures that Cisco Discovery Protocol packets use the IP address that has been previously assigned to an interface. Without this command, Cisco Discovery Protocol uses the IP address of the first available interface.
The conditions that an interface should satisfy to be the source interface are as follows:
When Cisco Discovery Protocol is enabled and the Cisco Discovery Protocol source interface has not been configured, then Cisco Discovery Protocol uses the IP address of the first available interface.
Examples
The following example configures Cisco Discovery Protocol to use the IP address that has been assigned to interface loopback 1.
Router# configure terminal Enter configuration commands, one per line. End with CNTL/Z. Router(config)# cdp source-interface loopback 1 Router(config)# exit Router#cdp timer
To specify how often the Cisco IOS software sends Cisco Discovery Protocol (CDP) updates, use the cdp timer command in global configuration mode. To revert to the default setting, use the noform of this command.
Command History
Release
Modification
10.3
This command was introduced.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support in a specific 12.2SX release of this train depends on your feature set, platform, and platform hardware.
Usage Guidelines
The trade-off with sending more frequent CDP updates to provide up-to-date information, is that bandwidth is used more often.
NoteThe cdp enable, cdp timer, and cdp run commands affect the operation of the IP on demand routing feature (that is, the router odr global configuration command). For more information on the router odr command, see the “On-Demand Routing Commands” chapter in the Cisco IOS IP Command Reference, Volume 2 of 3: Routing Protocols document.
Examples
In the following example, CDP updates are sent every 80 seconds, less frequently than the default setting of 60 seconds. You might want to make this change if you are concerned about preserving bandwidth.
cdp timer 80Related Commands
Command
Description
cdp enable
Enables CDP on a supported interface.
cdp holdtime
Specifies the amount of time the receiving device should hold a CDP packet from your router before discarding it.
cdp timer
Specifies how often the Cisco IOS software sends CDP updates.
router odr
Enables ODR on the hub router.
show cdp
Displays global CDP information, including timer and hold-time information.
cdp tlv
To configure location support in Cisco Discovery Protocol (CDP), use the cdp tlv command in global configuration mode or interface configuration mode. To disable the location support configuration, use the no form of this command.
Command Syntax in Global Configuration Mode
cdp tlv { app | location | location-server }
no cdp tlv { app | location | location-server }
Command Syntax in Interface Configuration Mode
cdp tlv { app [ tlvtype tlvtype value value ] | location | location-server }
no cdp tlv { app [ tlvtype tlvtype value value ] | location | location-server }
Syntax Description
app
Enables application Type-Length-Values (TLVs).
location
Enables location TLVs on CDP messages.
location-server
Enables location-server TLVs on CDP messages.
tlvtype tlvtype
(Optional) Configures application TLV type information. The range is from 1001 to 65535.
value value
Configures application TLV value information.
Usage Guidelines
To enable location-based services, information on the exact location of endpoint devices in the network is very essential. The information on the location of endpoint devices is delivered through Cisco devices using the CDP mechanism. To enable location support at the global level, use the cdp tlv command in global configuration mode. To enable location support on interfaces, use the cdp tlv command in interface configuration mode. If application TLVs are enabled on all interfaces, the TLVs are sent on all interfaces. Location TLVs in CDP are enabled by default. You can disable the storage of location TLVs by using the no cdp tlv location command. When you use the cdp tlv location command in global configuration mode, CDP starts sending periodic location information when the location TLV is enabled and the location information is available. When you use the cdp tlv location command in interface configuration mode, TLVs are sent along with the CDP messages periodically.
Examples
The following example shows how to configure location support for application TLVs in CDP at the global level:
Router(config)# cdp tlv appThe following example shows how to configure location support for application TLVs in CDP at an interface level:
Router(config)# interface fastethernet 0 Router(config-if)# cdp tlv app tlvtype 1002 value loc1clear cdp counters
To reset Cisco Discovery Protocol (CDP) traffic counters to zero, use the clear cdp counterscommand in privileged EXEC mode.
Command History
Release
Modification
10.3
This command was introduced.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support in a specific 12.2SX release of this train depends on your feature set, platform, and platform hardware.
Examples
The following example clears the CDP counters. The show cdp trafficoutput shows that all of the traffic counters have been reset to zero.
Router# clear cdp counters Router# show cdp traffic CDP counters: Packets output: 0, Input: 0 Hdr syntax: 0, Chksum error: 0, Encaps failed: 0 No memory: 0, Invalid packet: 0, Fragmented: 0clear cdp table
To clear the table that contains Cisco Discovery Protocol (CDP) information about neighbors, use the clear cdp table command in privileged EXEC mode.
Command History
Release
Modification
10.3
This command was introduced.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support in a specific 12.2SX release of this train depends on your feature set, platform, and platform hardware.
Examples
The following example clears the CDP table. The output of the show cdp neighbors command shows that all information has been deleted from the table.
Router# clear cdp table CDP-AD: Deleted table entry for neon.cisco.com, interface Ethernet0 CDP-AD: Deleted table entry for neon.cisco.com, interface Serial0 Router# show cdp neighbors Capability Codes: R - Router, T - Trans Bridge, B - Source Route Bridge S - Switch, H - Host, I - IGMP Device ID Local Intrfce Holdtme Capability Platform Port IDshow cdp
To display global Cisco Discovery Protocol (CDP) information, including timer and hold-time information, use the show cdp command in privileged EXEC mode.
Command History
Release
Modification
10.3
This command was introduced.
12.0(3)T
The output of this command was modified to include CDP Version 2 information.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support in a specific 12.2SX release of this train depends on your feature set, platform, and platform hardware.
12.2(33)SXI
This command was changed to add the optional vlan vlan keyword and argument.
Usage Guidelines
Cisco IOS Release 12.2(33)SXI and later releases allow you to limit the display of switch port information to the specified VLAN.
Examples
The following example shows that the current router is sending CDP advertisements every 1 minute (the default setting for the cdp timerglobal configuration command). Also shown is that the current router directs its neighbors to hold its CDP advertisements for 3 minutes (the default for the cdp holdtimeglobal configuration command), and that the router is enabled to send CDP Version 2 advertisements:
Router# show cdp Global CDP information: Sending CDP packets every 60 seconds Sending a holdtime value of 180 seconds Sending CDPv2 advertisements is enabledThe following example shows how to limit the displayed CDP information to a specific VLAN:
Router# show cdp vlan 11 Global CDP information: Sending CDP packets every 60 seconds Sending a holdtime value of 180 seconds Sending CDPv2 advertisements is enabledThe table below describes the significant fields shown in the display.
Table 1 show cdp Field Descriptions Field
Definition
Sending CDP packets every XX seconds
The interval (in seconds) between transmissions of CDP advertisements. This field is controlled by the cdp timer command.
Sending a holdtime value of XX seconds
The amount of time (in seconds) the device directs the neighbor to hold a CDP advertisement before discarding it. This field is controlled by the cdp holdtime command.
Sending CDPv2 advertisements is XX
The state of whether CDP Version-2 type advertisements are enabled to be sent. Possible states are enabled or disabled. This field is controlled by the cdp advertise v2 global configuration command.
Related Commands
Command
Description
cdp advertise-v2
Enables CDP Version 2 advertising functionality on a device.
cdp holdtime
Specifies the amount of time the receiving device should hold a CDP packet from your router before discarding it.
cdp timer
Specifies how often the Cisco IOS software sends CDP updates.
show cdp entry
Displays information about a specific neighbor device listed in the CDP table.
show cdp interface
Displays information about the interfaces on which CDP is enabled.
show cdp neighbors
Displays detailed information about neighboring devices discovered using CDP.
show cdp traffic
Displays information about traffic between devices gathered using CDP.
show cdp entry
To display information about a specific neighboring device discovered using Cisco Discovery Protocol (CDP), use the show cdp entrycommand in privileged EXEC mode.
Syntax Description
*
Displays all of the CDP neighbors.
device-name *
Name of the neighbor about which you want information. You can enter an optional asterisk (*) at the end of a device-name as a wildcard. For example, entering show cdp entry dev* will match all device names that begin with dev.
version
(Optional) Limits the display to information about the version of software running on the router.
protocol
(Optional) Limits the display to information about the protocols enabled on a router.
Command History
Release
Modification
10.3
This command was introduced.
12.2(8)T
Support for IPv6 address and address type information was added.
12.2(14)S
This command was integrated into Cisco IOS Release 12.2(14)S.
12.2(28)SB
This command was integrated into Cisco IOS Release 12.2(28)SB.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2(33)SXH
This command was integrated into Cisco IOS Release 12.2(33)SXH.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support in a specific 12.2SX release of this train depends on your feature set, platform, and platform hardware.
Examples
The following is sample output from the show cdp entrycommand. Information about the neighbor device.cisco.com is displayed, including device ID, protocols and addresses, platform, interface, hold time, and version.
Router# show cdp entry device.cisco.com Device ID: device.cisco.com Entry address(es): IP address: 10.1.17.24 IPv6 address: FE80::203:E3FF:FE6A:BF81 (link-local) IPv6 address: 4000::BC:0:0:C0A8:BC06 (global unicast) CLNS address: 490001.1111.1111.1111.00 Platform: cisco 3640, Capabilities: Router Interface: Ethernet0/1, Port ID (outgoing port): Ethernet0/1 Holdtime : 160 sec Version : Cisco Internetwork Operating System Software IOS (tm) 3600 Software (C3640-A2IS-M), Experimental Version 12.2 Copyright (c) 1986-2001 by cisco Systems, Inc. Compiled Wed 08-Aug-01 12:39 by joeuserThe table below describes the significant fields shown in the example.
Table 2 show cdp entry Field Descriptions Field
Definition
Device ID: device.cisco.com
Name or ID of the device.
Entry address(es):
The IP, IPv6 link-local, IPv6 global unicast, and CLNS addresses.
Platform:
Platform information specific to the device.
Interface: Ethernet0/1, Port ID (outgoing port): Ethernet0/1
Information about the interface and port ID interface.
Holdtime:
Holdtime length in seconds.
Version:
Information about the software version.
The following is sample output from the show cdp entry version command. Only information about the version of software running on device.cisco.com is displayed.
Router# show cdp entry device.cisco.com version Version information for device.cisco.com: Cisco Internetwork Operating System Software IOS (tm) 3600 Software (C3640-A2IS-M), Experimental Version 12.2 Copyright (c) 1986-2001 by cisco Systems, Inc. Compiled Wed 08-Aug-01 12:39 by joeuserThe following is sample output from the show cdp entry protocol command. Only information about the protocols enabled on device.cisco.com is displayed.
Router# show cdp entry device.cisco.com protocol Protocol information for device.cisco.com: IP address: 10.1.17.24 IPv6 address: FE80::203:E3FF:FE6A:BF81 (link-local) IPv6 address: 4000::BC:0:0:C0A8:BC06 (global unicast) CLNS address: 490001.1111.1111.1111.00Related Commands
Command
Description
show cdp
Displays global CDP information, including timer and hold-time information.
show cdp interface
Displays information about the interfaces on which CDP is enabled.
show cdp neighbors
Displays detailed information about neighboring devices discovered using CDP.
show cdp traffic
Displays traffic information from the CDP table.
show cdp interface
To display information about the interfaces on which Cisco Discovery Protocol (CDP) is enabled, use the show cdp interface command in privileged EXEC mode.
Command History
Release
Modification
10.3
This command was introduced.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support in a specific 12.2SX release of this train depends on your feature set, platform, and platform hardware.
Examples
The following is sample output from the show cdp interfacecommand. Status information and information about CDP timer and hold-time settings is displayed for all interfaces on which CDP is enabled.
Router# show cdp interface Serial0 is up, line protocol is up, encapsulation is SMDS Sending CDP packets every 60 seconds Holdtime is 180 seconds Ethernet0 is up, line protocol is up, encapsulation is ARPA Sending CDP packets every 60 seconds Holdtime is 180 secondsThe following is sample output from the show cdp interfacecommand with an interface specified. Status information and information about CDP timer and hold-time settings is displayed for Ethernet interface 0 only.
Router# show cdp interface ethernet 0 Ethernet0 is up, line protocol is up, encapsulation is ARPA Sending CDP packets every 60 seconds Holdtime is 180 secondsRelated Commands
Command
Description
show cdp
Displays global CDP information, including timer and hold-time information.
show cdp entry
Displays information about a specific neighbor device or all neighboring devices discovered using CDP.
show cdp neighbors
Displays detailed information about neighboring devices discovered using CDP.
show cdp traffic
Displays traffic information from the CDP table.
show cdp neighbors
To display detailed information about neighboring devices discovered using Cisco Discovery Protocol, use the show cdp neighbors command in privileged EXEC mode.
Syntax Description
type
(Optional) Interface type that is connected to the neighbors about which you want information; possible valid values are ethernet, fastethernet, gigabitethernet, tengigabitethernet, port-channel,and vlan.
number
(Optional) Number of the interface connected to the neighbors about which you want information.
detail
(Optional) Displays detailed information about a neighbor (or neighbors) including network address, enabled protocols, hold time, and software version.
Command History
Release
Modification
10.3
This command was introduced.
12.0(3)T
This command was modified. The output of this command using the detail keyword was expanded to include Cisco Discovery Protocol Version 2 information.
12.2(8)T
This command was modified. Support for IPv6 address and address type information was added.
12.2(14)S
This command was integrated into Cisco IOS Release 12.2(14)S. Support for IPv6 address and address type information was added.
12.2(14)SX
This command is supported in the Cisco IOS Release 12.2(14)SX. Support for this command was introduced on the Supervisor Engine 720.
12.2(17d)SXB
This command was modified. Support for this command was introduced on the Supervisor Engine 2.
12.2(28)SB
This command was integrated into Cisco IOS Release 12.2(28)SB.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support in a specific 12.2SX release of this train depends on your feature set, platform, and platform hardware.
12.4(25d)JAX
This command was integrated into Cisco IOS Release 12.4(25d)JAX. The output of this command was modified to display the host router's neighbor wireless LAN-Gigabit Ethernet port as “WGi” instead of “Gig”.
Usage Guidelines
The vlan keyword is supported in Cisco 7600 series routers that are configured with a Supervisor Engine 2.
The port-channel values are from 0 to 282; values from 257 to 282 are supported on the call switching module (CSM) and the firewall services module (FWSM) only.
Examples
The following is sample output from the show cdp neighbors command:
Router# show cdp neighbors Capability Codes:R - Router, T - Trans Bridge, B - Source Route Bridge S - Switch, H - Host, I - IGMP, r - Repeater Device ID Local Intrfce Holdtme Capability Platform Port ID device1 Eth 0 133 R 4500 Eth 0 device2 Eth 0 152 R AS5200 Eth 0 device3 Eth 0 144 R 3640 Eth0/0 device4 Eth 0 141 RP1 Eth 0/0 device5 Eth 0 164 7206 Eth 1/0The following sample output from the show cdp neighbors command displays details of the wireless LAN-Gigabit Ethernet port:
Router# show cdp neighbors Capability Codes:R - Router, T - Trans Bridge, B - Source Route Bridge S - Switch, H - Host, I - IGMP, r - Repeater Device ID Local Intrfce Holdtme Capability Platform Port ID device6 Gig 0 157 R S I C887VA-W- WGi 0The table below describes the fields shown in the display.
The following is sample output for one neighbor from the show cdp neighbors detailcommand. Additional detail is shown about neighbors, including network addresses, enabled protocols, and software version.
Router# show cdp neighbors detail Device ID: device.cisco.com Entry address(es): IPv6 address: FE80::203:E3FF:FE6A:BF81 (link-local) IPv6 address: 4000::BC:0:0:C0A8:BC06 (global unicast) Platform: cisco 3640, Capabilities: Router Interface: Ethernet0/1, Port ID (outgoing port): Ethernet0/1 Holdtime : 160 sec Version : Cisco Internetwork Operating System Software IOS (tm) 3600 Software (C3640-A2IS-M), Version 12.2(25)SEB4, RELE) advertisement version: 2 Duplex Mode: half Native VLAN: 42 VTP Management Domain: ‘Accounting Group’The table below describes the fields shown in the display.
Related Commands
Command
Description
show cdp
Displays global CDP information, including timer and hold-time information.
show cdp entry
Displays information about a specific neighbor device listed in the CDP table.
show cdp interface
Displays information about the interfaces on which CDP is enabled.
show cdp traffic
Displays information about traffic between devices gathered using CDP.
show cdp tlv
To display information about Cisco Discovery Protocol (CDP) Type-Length-Values (TLVs), use the show cdp tlvcommand in privileged EXEC mode.
show cdp tlv { app interface type number | location [ all | civic | elin ] [ interface type number ] | location-server [ interface type number ] }
Syntax Description
app
Displays application TLVs stored in CDP messages.
interface type number
Specifies the interface type and number.
location
Displays location information for TLVs.
all
(Optional) Displays location information for all TLVs.
civic
(Optional) Displays civic location information.
elin
(Optional) Displays emergency location identifier number (ELIN) location information.
location-server
Displays location-server information stored in CDP for one interface or for all interfaces.
Usage Guidelines
You can use the show cdp tlv command to verify the TLVs configured on CDP. The show cdp tlv command displays location-specific information for an interface, if an interface is specified; otherwise, it displays location-specific information for all interfaces. You can also choose to display location-specific information for civic, ELIN, or all TLVs.
Examples
The following example shows how to display location-specific information for all TLVs:
Router# show cdp tlv location civic interface gigabitEthernet 3/0/2 No CIVIC Location received from neighbor(switch1) Interface (GigabitEthernet3/0/2), Civic country code: US CA type: 3, Len: 9, Value: bangalore CA type: 24, Len: 6, Value: 560087 CA type: 25, Len: 18, Value: CessnaBusinessPark CA type: 34, Len: 13, Value: OuterRingRoadThe table below describes the significant fields shown in the display.
show cdp traffic
To display information about traffic between devices gathered using Cisco Discovery Protocol (CDP), use the show cdp trafficcommand in privileged EXEC mode.
Command History
Release
Modification
10.3
This command was introduced.
12.2(33)SRA
This command was integrated into Cisco IOS Release 12.2(33)SRA.
12.2SX
This command is supported in the Cisco IOS Release 12.2SX train. Support in a specific 12.2SX release of this train depends on your feature set, platform, and platform hardware.
Examples
The following is sample output from the show cdp traffic command:
Router# show cdp traffic Total packets output: 543, Input: 333 Hdr syntax: 0, Chksum error: 0, Encaps failed: 0 No memory: 0, Invalid: 0, Fragmented: 0 CDP version 1 advertisements output: 191, Input: 187 CDP version 2 advertisements output: 352, Input: 146The table below describes the significant fields shown in the display.
Table 6 show cdp traffic Field Descriptions Field
Definition
Total packets output
The number of CDP advertisements sent by the local device. Note that this value is the sum of the CDP Version 1 advertisements output and CDP Version 2 advertisements output fields.
Input
The number of CDP advertisements received by the local device. Note that this value is the sum of the CDP Version 1 advertisements input and CDP Version 2 advertisements input fields.
Hdr syntax
The number of CDP advertisements with bad headers, received by the local device.
Chksum error
The number of times the checksum (verifying) operation failed on incoming CDP advertisements.
Encaps failed
The number of times CDP failed to send advertisements on an interface because of a failure caused by the bridge port of the local device.
No memory
The number of times the local device did not have enough memory to store the CDP advertisements in the advertisement cache table when the device was attempting to assemble advertisement packets for transmission and parse them when receiving them.
Invalid
The number of invalid CDP advertisements received and sent by the local device.
Fragmented
The number of times fragments or portions of a single CDP advertisement were received by the local device instead of the complete advertisement.
CDP version 1 advertisements output
The number of CDP Version 1 advertisements sent by the local device.
Input
The number of CDP Version 1 advertisements received by the local device.
CDP version 2 advertisements output
The number of CDP Version 2 advertisements sent by the local device.
Input
The number of CDP Version 2 advertisements received by the local device.
Related Commands
Command
Description
show cdp
Displays global CDP information, including timer and hold-time information.
show cdp entry
Displays information about a specific neighbor device listed in the CDP table.
show cdp interface
Displays information about the interfaces on which CDP is enabled.
show cdp neighbors
Displays detailed information about neighboring devices discovered using CDP.
