CISCO DISCOVERY PROTOCOL (CDP)
+Layer 2 Protocol
+Cisco Properitary Protocol
+Used by Cisco Devices to discover other connected Cisco devices
+CDP Sends advertisements to directly connected devices
+BY DEFAULT ==> CDP IS ENABLED
PUNE_ROUTER>show cdp
Global CDP information:
Sending CDP packets every 60 seconds
Sending a holdtime value of 180 seconds
Sending CDPv2 advertisements is enabled
+ CDP Neighbor Output
PUNE_ROUTER#show cdp neighbors
Capability Codes: R - Router, T - Trans Bridge, B - Source Route Bridge
S - Switch, H - Host, I - IGMP, r - Repeater, P - Phone
Device ID Local Intrfce Holdtme Capability Platform Port ID
PUNE_LAN_SW Gig 0/0/0 152 S 2960 Fas 0/1
CHENNAI_ROUTER
Ser 0/1/0 150 R ISR4300 Ser 0/1/1
+ CDP Interfaces
PUNE_ROUTER#show cdp interface
Vlan1 is administratively down, line protocol is down
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
GigabitEthernet0/0/0 is up, line protocol is up
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
GigabitEthernet0/0/1 is administratively down, line protocol is down
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
GigabitEthernet0/0/2 is administratively down, line protocol is down
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
Serial0/1/0 is up, line protocol is up
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
Serial0/1/1 is administratively down, line protocol is down
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
PUNE_ROUTER#
+ CDP Disabled Globally
PUNE_ROUTER(config)#no cdp run
PUNE_ROUTER(config)#do wr
Building configuration...
[OK]
PUNE_ROUTER(config)#do show cdp
% CDP is not enabled
PUNE_ROUTER(config)#
+ CDP Disabled on an interface
PUNE_ROUTER(config)#int serial 0/1/0
PUNE_ROUTER(config-if)#no cdp enable
Thanks for Reading
NETWORK ENGINEER STUFF
