the CDP process might be not running properly on access point
or if the switch port is a trunk verify what is the native vlan and if it is permitted on the trunk and in STP forwarding state.
CDP should use the native vlan.
Hope to help
I see that you see other APs as CDP neighbors.
what is the config of the switch port where the missing neighbor is connected ?
sh run int fx/y
sh int fx/y switchport
And as John suggests what is the config of the access point (but it may be controlled by WLC as I see in your sh cdp nei)
Hope to help
Here is the sh run on
description Access Point Vlan 10.218.16.1 255.255.255.0
switchport access vlan 3526
switchport mode access
Here is the sh inter:
BU111371#sh interface fastEthernet 1/0/20
FastEthernet1/0/20 is up, line protocol is up (connected)
Hardware is Fast Ethernet, address is 0021.d7a1.3f16 (bia 0021.d7a1.3f16)
Description: Access Point Vlan 10.218.16.1 255.255.255.0
MTU 1500 bytes, BW 100000 Kbit, DLY 100 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Full-duplex, 100Mb/s, media type is 10/100BaseTX
input flow-control is off, output flow-control is unsupported
ARP type: ARPA, ARP Timeout 04:00:00
Last input never, output 00:00:03, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
291889 packets input, 40719292 bytes, 0 no buffer
Received 7121 broadcasts (0 multicast)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 0 multicast, 0 pause input
0 input packets with dribble condition detected
1738790 packets output, 862937791 bytes, 0 underruns
0 output errors, 0 collisions, 3 interface resets
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier, 0 PAUSE output
0 output buffer failures, 0 output buffers swapped out
I don't see any trouble on your configuration of the switch port.
I would try to restart the access point to see if anything changes.
Being the port an access port there no troubles with trunk encapsulation or native vlan mismatch.
Hope to help
I had a 2620 fast ethernet interface that would not send out cdp packets nor any multicast packets except those in the range of 22.214.171.124 255.255.255.0
It was a hardware failure.
I see WLC controller in CDP neig.
Are these AP LWAP ?
If so you may need to enable cdp from WLC.
> On top click on wireless
You will see the APs names.
> Click on the AP which is not in CDP
> Click on advance
and you will find the cdp enable click.
hope this helps
At the risk of sounding like a wise guy, Giuseppe suggested you look at the CDP config on the AP 5 days ago -- when you first started this thread.
Replied by: giuslar - Senior Network Engineer, Italtel S.p.A - Jan 9, 2009, 1:04pm PST
the CDP process might be not running properly on access point...