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Trouble to obtain ip via external DHCP

New Contributor III

My network is in a vlan environment, each SSID,the ZS1200 and a ZF R500 is a different Vlan. Further, i have a Windows DHCP server 2008 Standard with a scope for each vlan/ssid.

DHCP . .       . . . |Switch core|. . . . . .       . . . . . . . |Switch Distr.|
Server                          |                                                     |
Vlan 50                         |                                                     |
                                     |                                                     |              SSID1/Vlan205
                                     |                                                 ZF R500    ))))))))))
                                     |                                                 Vlan232
                               ZD1200                                                              SSID2/Vlan206
                               Vlan202                                                             ))))))))))

The ZD1200 is configured with ip controller 192.168.202.x Vlan 202, SSID1 Vlan 205 y SSID2 Vlan 206.

SSID1 should give the 192.168.205.x segment via scope DHCP external server.
SSID2 should give the 192.168.206.x segment via scope DHCP external server.
The DHCP server is in the segment 192.168.5.x.

The switch Core is WS-C3750X-24T-S, conects the ZD1200 in a trunk port:

stack3750#sh run int Gi2/0/3
Building configuration...
Current configuration : 123 bytes
interface GigabitEthernet2/0/3
description WLC RUCKUS
switchport trunk encapsulation dot1q
switchport mode trunk

The switch Distr. is WS-C2960S-48FPS-L, this conect the ZF R500 in a trunk port:

sw2-Piso2-O#sh run int Gi1/0/9
Building configuration...
Current configuration : 142 bytes
interface GigabitEthernet1/0/9
description AP-RUCKUS
switchport trunk native vlan 232
switchport mode trunk
spanning-tree portfast

in this port the native vlan is the vlan 232 (vlan ZF R500).

Ip helper DHCP is enabled in both switches.

when a user connects to SSID1 o SSID2, the conection is sucess but the user is not getting ip from external DHCP server.

I tried to enabling DHCP relay and option 82 in ZD1200 ( the option 82 is enabled in server DHCP) but the users not yet obtain ip.

I'll be attentive to your comments.

Contributor II

On the core switch, do you have a VI configured for each of those VLANs (205, 206)?  This would be the default gateway for those clients and IP helper should be configured within those virtual interfaces in order for DHCP discover packets to be re-directed to the DHCP server accordingly.

May want to provide the rest of the switch config and/or, have you tested the DHCP server to ensure that it is leasing IPs on those scopes?  A simple test could be connecting a PC directly to a switch port configured as access on vlans 205 and 206 and see if you get an IP, or creating a virtual interface on the access switch and set it to obtain an IP via DHCP.

New Contributor III
Hi Dionis,
The vlan 205 and 206 are configured in that switch core.
When the switchport is set in access mode vlan access 232 (vlan AP) and  conect mi pc in this port, i get ip, but when conect the ap en this port i'm not getting it.

i read your above comment, can u pls check port security on that switch port?

Contributor II
Mind sending me the rest of the switch configuration? Feel free to remove some of the private information you may have, such as passwords if not encrypted and IPs of the management side of things