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CDP

CDP
1.CDP會有安全性的疑慮,建議非必要還是關掉!
2.Data Link Layer, Multicast

S2950#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
Switch           Fas 0/8            145          S I      WS-C3750G-Gig 1/0/9

S2950#show cdp entry Switch
-------------------------
Device ID: Switch
Entry address(es):
  IP address: 192.168.1.150
Platform: cisco WS-C3750G-24T,  Capabilities: Switch IGMP
Interface: FastEthernet0/8,  Port ID (outgoing port): GigabitEthernet1/0/9
Holdtime : 131 sec

Version :
Cisco IOS Software, C3750 Software (C3750-IPSERVICESK9-M), Version 12.2(55)SE9, RELEASE SO                                             FTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2014 by Cisco Systems, Inc.
Compiled Mon 03-Mar-14 22:45 by prod_rel_team

advertisement version: 2
Protocol Hello:  OUI=0x00000C, Protocol ID=0x0112; payload len=27, value=00000000FFFFFFFF0                                             10231FF00000000000000169D993E80FF0000
VTP Management Domain: ''
Native VLAN: 1
Duplex: full
Management address(es):
  IP address: 192.168.1.150

S2950#show cdp neighbors fastEthernet 0/8
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
Switch           Fas 0/8            172          S I      WS-C3750G-Gig 1/0/9

S2950#show cdp neighbors detail
-------------------------
Device ID: Switch
Entry address(es):
  IP address: 192.168.1.150
Platform: cisco WS-C3750G-24T,  Capabilities: Switch IGMP
Interface: FastEthernet0/8,  Port ID (outgoing port): GigabitEthernet1/0/9
Holdtime : 170 sec

Version :
Cisco IOS Software, C3750 Software (C3750-IPSERVICESK9-M), Version 12.2(55)SE9, RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2014 by Cisco Systems, Inc.
Compiled Mon 03-Mar-14 22:45 by prod_rel_team

advertisement version: 2
Protocol Hello:  OUI=0x00000C, Protocol ID=0x0112; payload len=27, value=00000000FFFFFFFF010231FF00000000000000169D993E80FF0000
VTP Management Domain: ''
Native VLAN: 1
Duplex: full
Management address(es):
  IP address: 192.168.1.150




在特定介面關掉CDP
S2950(config)#interface fastEthernet 0/1
S2950(config-if)#no cdp enable

在Global關掉CDP
S2950(config)#no cdp run


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