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  • 1.  Using the conductor DCHP server for clients

    Posted 20 days ago

    I hit a brick wall with regard to using the conductor as a DHCP server. I am working on a migration from a controller based deployment that used a DHCP server for some of its SSIDs to a conductor-based deployment.

    From what I gathered so far, I cannot use the controller as DHCP server when used in cluster-mode. 

    I thought let me pivot to a deployment with DHCP on the conductors. The configuration seemed pretty straight forward but for the life of it, I can't get it to work properly.

    When checking a packet capture, I do see DHCP discovers, but they don't seem to make it to the conductor.

    The setup is simple:

    VLAN 201: is my controller and conductor VLAN, it has a default route

    VLAN 39: Is the VLAN that should use the conductor as DHCP server

    It is configured as below.

    interface vlan 39 
       no suppress-arp 
       ip address 192.168.39.253 255.255.255.0 
       ip helper-address 10.20.201.100 << conductor VRRP IP
    !
    interface vlan 201 
       ip address 10.20.201.201 255.255.255.0 

    Am I missing something? I found other airheads threads, saying don't use the conductor as DHCP server for clients, but nothing was really clear, the documentation is pretty minimal too.

    Hope you have some input.



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    Martijn van Overbeek
    Architect, Netcraftsmen a BlueAlly Company
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  • 2.  RE: Using the conductor DCHP server for clients

    Posted 20 days ago

    Conductors aren't DHCP servers, and for that matter aren't meant to be in the datapath of the client.  Controllers can be DHCP servers, but shouldn't be used as such for various reasons, and very much shouldn't be used when clustering since AOS 8 has zero concept of DHCP redundancy.  AOS 10 does a better job of enabling DHCP support on the gateway when we're talking about the "default gateway" operational mode.

    DHCP should be handled by either a dedicated DHCP server or, worse case, a switch/router/firewall/etc.



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    Carson Hulcher, ACEX#110
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  • 3.  RE: Using the conductor DCHP server for clients

    Posted 20 days ago

    Although I understand your points, I am still a bit puzzled why am I allowed to configure DHCP? Is it only for DHCP for APs, functionally I would think DHCP for APs or Clients makes no difference. I



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    Martijn van Overbeek
    Architect, Netcraftsmen a BlueAlly Company
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  • 4.  RE: Using the conductor DCHP server for clients

    Posted 20 days ago

    Because nothing was done to make the DHCP configuration be context sensitive to determine what device you are attempting to make that change on.



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    Carson Hulcher, ACEX#110
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  • 5.  RE: Using the conductor DCHP server for clients

    Posted 20 days ago

    You can make one of the controllers in the cluster a DHCP server. But as was mentioned there is no redundancy.  There is also a limit I believe on the total number of addresses that can be served 



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    Stewart Smith
    ACMX, ACDX, ACCP, ACSA
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