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Aironet can't assign ip's to clients

sotspinos
Level 1
Level 1

Hey guys,

my current setup is the following. 

1. A router (192.168.1.1) connects to a switch.

2. A cisco wlan 2500 controller(192.168.1.35) connects to the switch.

3. Two aironet's 2700 (192.168.1.53) and (192.168.1.54) connect to the switch.

My SSID is visible, and I have no authentication for now. 

Every time any device is trying to connect on the aironet's SSID I get failed to get IP.

Could you please advise me what should I do next?

1 Accepted Solution

Accepted Solutions

Try checking your router configuration, and verify if the WLC is able to reach the router.

To add, if you are using an MBSSID setup(Multiple SSIDs) make sure there is a L3 interface in the router that corresponds to that subnet.

Though, why not use the WLC as the DHCP Server
It will put less strain on the router

 

View solution in original post

8 Replies 8

johnd2310
Level 8
Level 8

Hi,

 

Which device on your network is the DHCP server?

 

John

**Please rate posts you find helpful**

Sandeep Choudhary
VIP Alumni
VIP Alumni

Hi,

1. Which device providing teh IP to wireless clients?

2. Did you enter the DHCP ip on dynamic interface on controller ?

***If you defined or providing IP via internal dhcp server(WLC) then u must enable DHCP Proxy.

Regards

LJ Gabrillo
Level 5
Level 5

Try this:

1. Check the controller configuration, Go to Controller->Interfaces

Check if your PRIMARY DHCP Server is pointed
-If you want your router to be the DHCP, well place the router's IP
-If you want the WLC to be the DHCP Server, well put its own IP(Mgmt) there :)

Additionally, Make sure DHCP Proxy is enabled (through this is default)

 

2. Lastly, check your switch, you may have DHCP snooping configured. (If ever your router is the DHCP Server)

Saurav Lodh
Level 7
Level 7

Troubleshooting : The following debug command will shows controller receiving a DHCP request from a client , transmitting a DHCP request to the DHCP server, receiving a reply from the DHCP server, and sending a DHCP offer to the client.

    (Cisco Controller) >debug dhcp message enable

Thank you for your answers.

So far:

 

debug dhcp - my android device is trying to connect on the network:

 

*DHCP Socket Task: Jul 18 15:10:28.719: f0:25:b7:9e:30:f0 DHCP option: vendor class id = dhcpcd-5.5.6 (len 12)  
*DHCP Socket Task: Jul 18 15:10:28.719: f0:25:b7:9e:30:f0 DHCP option: hostname = android-6eb4f2d7b58ddf6d (len)
*DHCP Socket Task: Jul 18 15:10:28.719: f0:25:b7:9e:30:f0 DHCP option: 55 (len 10) - skipping                   
*DHCP Socket Task: Jul 18 15:10:28.719: f0:25:b7:9e:30:f0 DHCP options end, len 81, actual 73                   
*DHCP Socket Task: Jul 18 15:10:28.719: f0:25:b7:9e:30:f0 DHCP intf:management dhcp proxy mode enabled          
*DHCP Socket Task: Jul 18 15:10:28.719: f0:25:b7:9e:30:f0 DHCP intf:management dhcp proxy mode enabled          
*DHCP Socket Task: Jul 18 15:10:28.719: f0:25:b7:9e:30:f0 DHCP Forwarding DHCP packet (340 octets)             1
*DHCP Socket Task: Jul 18 15:10:33.672: 58:94:6b:92:6b:08 DHCP option len (including the magic cookie) 72       
*DHCP Socket Task: Jul 18 15:10:33.672: 58:94:6b:92:6b:08 DHCP option: message type = DHCP INFORM               
*DHCP Socket Task: Jul 18 15:10:33.672: 58:94:6b:92:6b:08 DHCP option: 61 (len 7) - skipping   

 

My router ip is: 192.168.1.1

In my cico wlan controller under wlan on the general tab I have : inetrface/inter group AS management

In the conroller --> interfaces  --> management I have the following:

interface address

vlan ident: 0

ip address: 192.168.1.35

netmask: 255.255.255.0

Gateway: 192.168.1.1

 

DHCP information

Primary DHCP Server: 192.168.1.1

DHCP proxy mode enable

So far while I'm trying to connect on the SSID i get failed to get ip.

Try checking your router configuration, and verify if the WLC is able to reach the router.

To add, if you are using an MBSSID setup(Multiple SSIDs) make sure there is a L3 interface in the router that corresponds to that subnet.

Though, why not use the WLC as the DHCP Server
It will put less strain on the router

 

Thank you all, and thanks Isgabrillo. How I missed that :)!

Glad to help :D

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