DSLAM IES-1248-51A Issues

CDJ Posts: 2  Freshman Member
First Comment
edited April 2021 in Security
The Dslam IES01248 & UAG 5100
The ADSL Modem PH660 were set on bridge mode with LLC. When the adsl modem is switched on, the WLan and LAN IP address is not able obtained from the UAG's DHCP( Some of the adsl modem take a long time to get the DHCP from UAG. Some of them does not get any IP at all. Some gets the adsl modem's DHCP  Port binding has been set to PVC "0" to all Lan port & AP of the modem. Can someone assist?


  • Blabababa
    Blabababa Posts: 151  Master Member
    First Anniversary Friend Collector First Answer First Comment
    What your topology looks like. Can you describe the topology further or draw a sketch to explain?
    About DHCP problem, it will be more clear if you can capture the packets from LAN/WLAN hosts.

    Moreover, you can cross check  by connecting your PC/Host to the UAG5100 directly. It helps to narrow down what the problematic device is 
  • CDJ
    CDJ Posts: 2  Freshman Member
    First Comment
    Thanks for your reply. 

    The guest is on vlan10. There is no issue on the AP(NWA5123) which are controlled by the UAG5100. The issue is at the adsl modem was not immediately get DHCP server. I tried to remove the VLAN10 at one of the port Dslam... it works first perfectly under Then I configured the GS1900 switch port to vlan10 only and Dslam to be under IP address of vlan10, 

  • Zyxel_Cooldia
    Zyxel_Cooldia Posts: 1,444  Zyxel Employee
    First Anniversary 10 Comments Friend Collector First Answer
    Hi @CDJ,
    Can you capture packets on UAG-5100 VLAN 10 interface(from ADSL modem client).
    The following is DHCP Interaction between server and client.
    DHCP Client-----------------------------------------------------DHCP Server
    1.                      discover =>
    2.                      <=offer
    3.                      request =>
    4.                      <= ack      
    Here we would like to confirm the DHCP server and client interaction.
    The flow initial on client side, make sure UAG-5100 receive “discover” packets from ADSL modem client, after that UAG-5100 response “offer” to the client,
    It must complete the process to get the IP from DHCP server. All in all, it would be helpful to narrow down this issue if we can see the DHCP interaction packets.

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