Hello,
I have a 3845 enabled for CDP connected to a stack of 3750 switches. From the router, i dont see any CDP neighbors. From the switch, i can see the router as neighbor. Why isn't the switch showing as a neighbor from the router side?
san-rt-rogers-01#sh cdp traffic
CDP counters :
Total packets output: 8349, Input: 0
Hdr syntax: 0, Chksum error: 0, Encaps failed: 0
No memory: 0, Invalid packet: 0, Fragmented: 0
CDP version 1 advertisements output: 90, Input: 0
CDP version 2 advertisements output: 8259, Input: 0
san-rt-rogers-01#sh cdp in
san-rt-rogers-01#sh cdp interface
GigabitEthernet0/0 is up, line protocol is up
Encapsulation ARPA
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
GigabitEthernet0/1 is administratively down, line protocol is down
Encapsulation ARPA
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
Serial4/0 is up, line protocol is up
Encapsulation HDLC
Sending CDP packets every 60 seconds
Holdtime is 180 seconds
san-rt-rogers-01#
san-rt-rogers-01#sh 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
san-rt-rogers-01#
san-sw-lr-02#sh 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
san-sw-lr-01.nucomm.net
Gig 1/0/1 157 R S I WS-C3750- Gig 1/0/1
san-rt-rogers-01.yourdomain.com
Fas 1/0/1 142 R S I 3845 Gig 0/0
SAN-CORE-SW-02 Fas 3/0/47 124 S I WS-C3750E Fas 0
san-sw-lr-02#
