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Many DHCP scopes on one VLAN segment - it that possible ?

  • 1.  Many DHCP scopes on one VLAN segment - it that possible ?

    Posted 02-16-2018 09:44
    Hello Community !

    I am wandering, if the following setup is possible to work:
    1. We have a set (let's say 5) of typical /24 subnets.
    2. There are separate DHCP pools defined for each subnet on single MS DHCP server.
    3. We have a router configured for DHCP relaying for each subnet and separate, untagged interface for each vlan.

    The goal is to have one 'big' network segment with single VLAN ID, having clients in this VLAN addressed with different scopes.

    At first it seems that such network config is asking for trouble, but I've heard people saying that it worked for them.

    The main problem is that subnet re-design is not an option.
    The switching is pure EXOS, vlans routing is done using Juniper SRX.

    Did you have any similar experiences ? Or do you have any ideas how to to it ?

    Thanks in advance for any feedback...

    Robert



  • 2.  RE: Many DHCP scopes on one VLAN segment - it that possible ?

    Posted 02-16-2018 09:49
    MS DHCP server knows mac-addresses of all devices that are connected?
    What if a new device will be connected? From which scope will he get an IP?


  • 3.  RE: Many DHCP scopes on one VLAN segment - it that possible ?

    Posted 02-16-2018 10:02
    I guess MS DHCP should know all MACs.
    I don't know - there is one DHCP server and many scopes.
    Maybe there is a way to direct specific DCHP pool traffic (or many pools) to one router interface ?


  • 4.  RE: Many DHCP scopes on one VLAN segment - it that possible ?

    Posted 02-16-2018 10:50
    Maybe you're looking for "super scopes" on MS DHCP?


  • 5.  RE: Many DHCP scopes on one VLAN segment - it that possible ?

    Posted 09-08-2021 20:23

    It is possible but it still does not work for me. Help

    I follow this

    https://extremeportal.force.com/ExtrArticleDetail?an=000056776&q=dhcp%20super%20scope

    And this

    https://documentation.extremenetworks.com/EOS_CLI/S-K-Series/S-K-7100_CLI_Guide/r_ip_dhcp_relay_information_option_link_selection.shtml?_ga=2.180551463.1457752191.1630679678-1276880935.1624384570

    and this is my setting

    --------------------------------------------------------------------------

    interface vlan.0.40
      ip address 10.9.4.1 255.255.254.0 primary
      ip address 10.9.14.1 255.255.254.0 secondary
      ip helper-address 10.0.0.x
      ip helper-address 10.9.0.xx
      ip dhcp relay information option
      ip dhcp relay information option link-selection 10.9.14.0 mac 1C1BB5BB5A44
      ip dhcp relay information option link-selection 10.9.14.0 mac 5C3A45
      no shutdown
      exit

    ----------------------------------------------------------------



  • 6.  RE: Many DHCP scopes on one VLAN segment - it that possible ?

    Posted 02-16-2018 10:50
    Sure, looks like it is about "super scopes" - thank you, mp2014 !