Morning
We have 2 Cisco 5508 WLCs, we have around 50 1142N APs across the campus, all of which use DHCP and PoE without any issues.
The WLCs are configured as DHCP relay agents which works perfectly well for both the APs and Clients.
We had a need for an additional AP, so we purchased a 2820i, ran a new cable which terminated into a Cisco 3750 switch which is already supporting several of the said 1142n APs.
The 3750 switch does not provided enough power for the newer AP so I also purchased an inline power injector - which works fine.
I have never had to pre-stage an AP before, so as before the new AP was installed and powered on. I was expecting it to mimic what every other AP has done for the last several years - get a DHCP address and join the controller - NOPE!!!
So in summary:
Yes, all other APs joined to that switch are able to get a DHCP address, all other APs tested on the very same port of that same switch are able to get a DHCP address - just not this AP.
If I console into the AP and debug DHCP events I can see that DHCP requests are indeed being sent, but not responded to:
[02/20/2018 23:26:26.7100] wired0 emac 2: link up
[02/20/2018 23:26:26.7600] wired0: link up
[02/20/2018 23:26:26.8100] wired0: started
[*02/20/2018 23:26:26.8635] aptrace_register_sysproc_fn: duplicate registeration for 'wired'
[*02/20/2018 23:26:27.6503] chatter: DHCP-EVT: Sending DHCP discover packet length 346 bytes
[*02/20/2018 23:26:27.6503] chatter: DHCP-PAK: Sent DHCP_DISCOVER pak:
[*02/20/2018 23:26:27.6503] chatter: sent pkt source: 0.0.0.0, destination: 255.255.255.255
[*02/20/2018 23:26:27.6503] chatter: UDP sport: 68, dport: 67, length: 312
[*02/20/2018 23:26:27.6503] chatter: DHCP op: 1, htype: 1, hlen: 6, hops: 0
[*02/20/2018 23:26:27.6503] chatter: xid: 7cd9e03e, secs: 0, flags: 0
[*02/20/2018 23:26:27.6503] chatter: client: 0.0.0.0, your: 0.0.0.0
[*02/20/2018 23:26:27.6504] chatter: srvr: 0.0.0.0, gw: 0.0.0.0
[*02/20/2018 23:26:30.8648] Waiting for uplink IPv4/IPv6 configuration
[*02/20/2018 23:26:35.8657] Waiting for uplink IPv4/IPv6 configuration
[*02/20/2018 23:26:40.8666] Waiting for uplink IPv4/IPv6 configuration
[*02/20/2018 23:26:41.8667] Resetting wired0, if[02/20/2018 23:26:41.9000] wired0: stopped
config down up
If from console I do a 'sho arp', it does just that and returns dozens of IP addresses from across the wireless network, so broadcasts are working, it just can't seem to get it's own IP address via a DHCP broadcast.
I have run 'Wireshark' on both DHCP servers and can see no requests from the AP's MAC address, though I can see other requests from devices on the wireless network being properly relayed through the controllers to the DHCP servers. So it can't be a relay problem.
If from console I enter a static address, subnet mask and the IP of the default gateway on the AP - it will IMMEADIATELY find both controllers and go through the automated process of joining with out issue. Clients are then able to use that AP, again without issue.
[*02/21/2018 10:33:53.4489] AP IPv4 Address updated from 0.0.0.0 to 172.20.255.230
[*02/21/2018 10:33:53.4561] dtls_init: Use MIC device cert
[*02/21/2018 10:33:53.4564] dtls_init: Use MIC device cert private key
[*02/21/2018 10:33:53.4565]
[*02/21/2018 10:33:53.4565] CAPWAP State: Init
[*02/21/2018 10:33:53.4569]
[*02/21/2018 10:33:53.4569] PNP is not required, Starting CAPWAP discovery
[*02/21/2018 10:33:53.4569]
[*02/21/2018 10:33:53.4571]
[*02/21/2018 10:33:53.4571] CAPWAP State: Discovery
[*02/21/2018 10:33:53.4617] Discovery Request sent to 172.20.255.201, discovery type STATIC_CONFIG(1)
[*02/21/2018 10:33:53.4630] Discovery Request sent to 255.255.255.255, discovery type UNKNOWN(0)
[*02/21/2018 10:33:53.4630]
[*02/21/2018 10:33:53.4630] CAPWAP State: Discovery
[*02/21/2018 10:33:53.4635] Discovery Response from 172.20.255.201
[*02/21/2018 11:05:01.0004] Discovery Response from 172.20.255.202
[*02/21/2018 11:05:01.0001] Discovery Response from 172.20.255.201
[*02/21/2018 11:05:01.0000]
[*02/21/2018 11:05:01.0000] CAPWAP State: DTLS Setup
[*02/21/2018 11:05:01.1328] dtls_load_ca_certs: LSC Root Certificate not present
[*02/21/2018 11:05:01.1328]
[*02/21/2018 11:05:01.2326]
[*02/21/2018 11:05:01.2326] CAPWAP State: Join
[*02/21/2018 11:05:01.2339] Sending Join request to 172.20.255.201 through port 5264
[*02/21/2018 11:05:01.2373] Join Response from 172.20.255.201
[*02/21/2018 11:05:01.3126] HW CAPWAP tunnel is ADDED
[*02/21/2018 11:05:01.3258]
[*02/21/2018 11:05:01.3258] CAPWAP State: Image Data
[*02/21/2018 11:05:01.3562] do NO_UPGRADE, part2 is active part
[*02/21/2018 11:05:01.3609]
[*02/21/2018 11:05:01.3609] CAPWAP State: Configure
[*02/21/2018 11:05:01.3640] NO-ENC-PROVIDER for DOT11R_WLC_MAC_IP_PAYLOAD
[*02/21/2018 11:05:02.0198] Started Radio 0
[*02/21/2018 11:05:02.0389] DOT11_DRV[0]: set_channel Channel set to 1
[*02/21/2018 11:05:02.9272] DOT11_DRV[0]: set_channel Channel set to 1
[*02/21/2018 11:05:04.1417] Started Radio 1
[*02/21/2018 11:05:04.1647] DOT11_DRV[1]: set_channel Channel set to 36
[*02/21/2018 11:05:05.0840] DOT11_DRV[1]: set_channel Channel set to 36
[*02/21/2018 11:05:06.3229] Discarding msg CAPWAP_WTP_EVENT_REQUEST(type 9) in CAPWAP state: Configure(8).
[*02/21/2018 11:05:06.3230] Discarding msg CAPWAP_WTP_EVENT_REQUEST(type 9) in CAPWAP state: Configure(8).
[*02/21/2018 11:05:06.3231] Discarding msg CAPWAP_WTP_EVENT_REQUEST(type 9) in CAPWAP state: Configure(8).
[*02/21/2018 11:05:06.3231] Discarding msg CAPWAP_WTP_EVENT_REQUEST(type 9) in CAPWAP state: Configure(8).
[*02/21/2018 11:05:06.3232] Discarding msg CAPWAP_WTP_EVENT_REQUEST(type 9) in CAPWAP state: Configure(8).
[*02/21/2018 11:05:06.4150] DOT11_DRV[0]: set_channel Channel set to 1
[*02/21/2018 11:05:07.4264] DOT11_DRV[1]: set_channel Channel set to 36
[*02/21/2018 11:05:08.3442] DOT11_DRV[1]: set_channel Channel set to 36
[*02/21/2018 11:05:09.4703]
[*02/21/2018 11:05:09.4703] CAPWAP State: Run
[*02/21/2018 11:05:09.5009] CAPWAP HW tunnel params changed, UPDATING the existing
[*02/21/2018 11:05:09.5559] AP has joined controller Cisco5508_WLC_Primary
I have checked the VLAN config which is on the switches, made sure the IP Helper Addresses are correct, basically gone through everything I can think of - still no closer to figuring this out. It has to be said the Cisco literature is pretty base and of no use when troubleshooting this issue.
Anyone else had this problem?
