Wireless Access

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Access network design for branch, remote, outdoor, and campus locations with HPE Aruba Networking access points and mobility controllers.
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External DHCP issue

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  • 1.  External DHCP issue

    Posted Sep 27, 2013 11:27 AM

    I have setup a new DHCP server just for the wireless clients. In the setup I have the address of the server setup as an IP Address Helper. The controller cannot see the server. I have even setup a VLAN IP of one of the scopes on the server. I cannot ping the IP from the scope on the controller. If I take a laptop assign the same IP that is assigned for the controller I can ping the laptop and from the laptop I can ping the server. I take the laptop out and have the controller in place of the laptop and cannot ping it or ping the server from the controller. TAC suggested giving the controller an IP on the same subnet as the server, which did not help. Just seeing if some one else has any suggestions. Thanks in advance.



  • 2.  RE: External DHCP issue

    Posted Sep 27, 2013 12:40 PM

    What is the ip of the DHCP server?  connect the controller to the network and post the output of

    (controller_140) #show ip route



  • 3.  RE: External DHCP issue

    Posted Sep 30, 2013 10:12 AM

    When we had Aruba deploy the system they said all we needed was a default route back to our core switch and from there it is forwarded.



  • 4.  RE: External DHCP issue

    EMPLOYEE
    Posted Sep 30, 2013 10:29 AM
    @jcameron wrote:

    When we had Aruba deploy the system they said all we needed was a default route back to our core switch and from there it is forwarded.

    Jcameron,

     

    Whatever is doing routing on that user subnet needs to be able to ping the DHCP server, NOT the controller.  Only a captive portal WLAN requires that an ip address be on the controller's interface on that VLAN.  If you are using 802.1x, and you are just bridging the user traffic to another layer 3 switch, the layer 3 switch has the ip address on that subnet, does the routing and has the ip helper-address command.  That layer 3 switch needs to be able to ping the DHCP server, NOT the Aruba controller, because it is just bridging traffic.

     

    If, on the other hand, the controller is the default gateway for your clients, the controller needs the ip address, helper address and should be able to ping the DHCP server.  Your clients should also be permitting DHCP traffic with an "any any service dhcp" statement in the role.