Ping works! But Join not. Why?

[Totardo Tobing]

Hello folks, I have some problems please help me,

My access point won't join to my my WLC. I'm pinging the AP from the WLC is reply. But the AP won't join. Why is that?

Thank you.

[Scott Fella]

There can be many variable to why the ap is not joining. Ping only test for connectivity. You need to understand the requirements for an ap to join and how to setup your wlc and your swicthports. The wlc time must be set correctly and the country code on the wlc and ap must match. These are the basic.

Here is a doc that will help you.

http://www.cisco.com/en/US/products/ps6366/products_tech_note09186a00808f8599.shtml

Sent from Cisco Technical Support iPhone App

[George Stefanick]

To piggy back on Scotts reply.

The AP has a IP address. In fact, if it hasnt join the controller you will see the pings will stop repsonding after a minute ; you will lose like 4 -7 pings becuase the ap is in the hunting process and will soft reboot if it doesnt find the controller.

[Saravanan Lakshmanan]

one AP not joining or none of them joining.

AP, WLC model?

WLC code?

Monitor>> Statistics>> AP Join. get the screen for that AP.

AP#debug capwap console cli

AP#test capwap controller ip

With above command in place run below debugs.

AP#debug capwap client error

AP#debug capwap client event

[Totardo Tobing]

Thanks to you all. Nice to have you guys around. You are really helpful.

@Scott fella, thank you for sharing that link, I'm reading it right now. But, now I gain many question. >.<

@George Stefanick: Yes, I know. The access point is cycling and cycling again when it unable contact the WLC.

@Saravanan:

AP, WLC model = 1140, 5500 series

WLC code = 6.0.116.0

Monitor>> Statistics>> AP Join. get the screen for that AP.

-- I don't have that AP on this screen.

AP#debug capwap console cli

AP#test capwap controller ip

With above command in place run below debugs.

AP#debug capwap client error

AP#debug capwap client event

--- The access point already mounted in 8 metres above us. We can't telnet neither console or enters this commands.

Is there any debug commands that can be used in this situation?

[Scott Fella]

The best way to really tell what is going on is to console into the ap.  Are you sure that these aps are lightweight and not autonomous?  If the AP's are autonomous, they will not join the WLC and you will need to convert that.  Issue a cdp neighbor on the switchport and see what type of ap the 1140 is.  You are looking for an AIR-LAP114X not an AIR-AP-114x.

[George Stefanick]

flip that ap over ... what is the full model number

[George Stefanick]

another easy way is put the ap on the same subnet of the wlc managment ip address.

[Saravanan Lakshmanan]

on wlc, can run capwap commands to see what's going on. if AP and WLC on different subnet with no L3 discovery mechanism in place or AP doesn't have an ip then nothing will be showe here. either bring the AP to same subnet as WLC management or use ip-helper and forward udp 5346 & 5347 then run below commands on wlc.

WLC>debug mac -- this can be skipped if only one AP is trying to join wlc.

WLC>debug capwap error enable

WLC>debug capwap event enable

[Scott Fella]

You mean 5246 & 5247:)

Sent from Cisco Technical Support iPhone App

[Saravanan Lakshmanan]

Sorry, thanks for correcting it.

[Totardo Tobing]

So hard to understand the join-process of an AP to a WLC. This is what I concern, please correct me guys:

Basic requirement:

AP basic requirement:

1. Put an IP address to AP via: Static configuration or get an IP address via DHCP mechanism + options 43 .

2. Put a configuration in access port of a switch that will be used to connect the LAP. Use command switchport mode access, switchport access vlan ...

3. Plug the access point to switch.

4. Access points reboots.

Start of CAPWAP process:

5. After finishing reboots process, AP gather / discover any potential WLCs around him using a discovery-request packet via: Its static configured primary, secondary or tertiary controller address; via DHCP options 43 value that he receive from get from point 1, via DNS or via subnet broadcast (255.255.255.255).

6. A list of potentially WLCs now created. Specifically, A list of potentially (Interface management of WLCs)

7. AP Sending discovery request messages to each IP address of the Interface-management that he found in point 6.

8. After sending discovery request, the access points will receive a discovery response, which each of discovery response message include the information about AP-management interface if the AP-management interface is created in the WLC.

8. Next,AP sending join request to the WLC and also send his certificate. WLC authorize this.

9. If AP is authorized then AP sending configuration request but if he knows that his software version is different with WLC.

So there are 3 types of process in LWAPP:

1. Discovery phase

2. Join phase

3. Configuration phase

Discovery phase is using discovery-request and discovery-response.

Join phase is using join-request and join-response

Configuration phase is using configuration-request and configuration-response

Discovery phase is for:

1. Looking / knowing / discovering interface-management IP address

2. Looking / knowing / discovering Interface-AP-Manager IP address too

Usefull debug commands in this process: debug capwap events enable

Join phase is for:

1. Validating AP's certicate

Usefull debug commands in this process: debug capwap events enable, debug pm pki enable

Configuration phase is for:

1. Matching software version on AP and WLC.

Useful debug commands in this process: debug capwap events enable.

So where these command should be placed according to 3 phases of CAPWAP?

WLC>debug mac -- this can be skipped if only one AP is trying to join wlc.

WLC>debug capwap error enable

WLC>debug capwap event enable

Kind a confuse to get things straight up here

Thanks a lot mate

[George Venianakis]

Hi Totardo,

It seems that you haven't your answer yet, if I'm not mistaken.

Anyway, in order to simplify things for you:

1) YOU HAVE to make sure that your APs are in lightweight mode and NOT in autonomous mode. If your APs are in autonomous mode you have to convert their boot image to the appropriate leightweight.

2) As far as the controller is concerned, and to state the obvious, make sure that your Controller is in "Master Controller Mode" as this is required for the initial registration from the AP to the WLC (After registering all your APs you can disable this feature). This is configured under Controller tab-->Advanced-->Master Controller Mode.

Hope this helped.

Cheers.