vWLC and dhcp problem

[s.ermolaev]

Hi, I have some problems with dhcp.I have 8.0.100.0 vWLC. My ap joined to the controller. Clients connected, but cannot receive ip address. I know, what are exist some methods to receive address, with DHCP Proxy Mode and without, then you just need to prescribe ip helper-address on int vlan. I try both of them, but nothing helps. 

[Saurav Lodh]

Dhcp and client issues troubleshoot

http://www.cisco.com/c/en/us/support/docs/wireless/4400-series-wireless-lan-controllers/107585-client-con.html

[Freerk Terpstra]

You are using the vWLC, which means that all your access-points should be in "flex-connect" mode. My advise is to make your SSID's "local switched" so that the client traffic gets bridged on the switchport (dot1Q trunk) directly. Than you need to configure the VLAN ID's on the access-point or flex-connect group in the WLC. If you have all the this configuration in place, you need to configure some DHCP relaying on your SVI (vlan interfaces) so the the client can actually gets an IPv4 address. I recommend to uncheck the option "DHCP required" on the SSID on the WLC.

This should get your network running. If it still does not work I would start troubleshooting on the WLC to see if the client is actually associated and authenticated (if you don't use any L3 security mechanism) if that is the case you should see the clients MAC address on the switchport. If the client by then still does not receive an IPv4 address, you need to troubleshoot the DHCP / SVI configuration on the switch/router and even maybe on the DHCP server itself.

[Abhishek Abhishek]

When Layer 3 mode on the controller was developed, a new Layer 3 interface called AP-manager was introduced. In Layer 3 mode, the LAPs would DHCP an IP address first and then send their discovery request to the management interface using IP addresses (Layer 3). This allowed the LAPs to be on a different subnet than the management interface of the controller. Layer 3 mode is the dominate mode today. Some controllers and LAPs can only perform Layer 3 mode.