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Crazy DHCP, please give me some help! RRS feed

  • Question

  • Please I am about to cry here, I am facing this problem for 1 week now and you are my last hope before getting fired.

    My DHCP is not working properly. It gives ramdonly the correct IP but sometimes some computers get 169 IP address.

    My situation is:

    I have an ISP managed router here, where the internet comes from and then it connects to my VPN JUNIPER SRX220 (IP 10.196.24.1) which is my VPN connection to Korea (headoffice).

    When I do an ipconfig /all on a working machine I get the following result:

    Ethernet adapter Conexão local:
    
       Connection-specific DNS Suffix  . :
       Description . . . . . . . . . . . : Realtek PCIe GBE Family Controller
       Physical Address. . . . . . . . . : F4-8E-38-E6-6E-70
       DHCP Enabled. . . . . . . . . . . : Yes
       Autoconfiguration Enabled . . . . : Yes
       Link-local IPv6 Address . . . . . : fe80::9824:a186:5bb7:28c7%13(Preferred)
       IPv4 Address. . . . . . . . . . . : 10.196.24.88(Preferred)
       Subnet Mask . . . . . . . . . . . : 255.255.255.0
       Lease Obtained. . . . . . . . . . : segunda-feira, 15 de maio de 2017 08:34:3
    9
       Lease Expires . . . . . . . . . . : terça-feira, 16 de maio de 2017 14:15:34
       Default Gateway . . . . . . . . . : 10.196.24.1
       DHCP Server . . . . . . . . . . . : 10.196.24.1
       DHCPv6 IAID . . . . . . . . . . . : 301239864
       DHCPv6 Client DUID. . . . . . . . : 00-01-00-01-1F-D0-82-E1-F4-8E-38-E6-6E-70
    
       DNS Servers . . . . . . . . . . . : 10.196.24.31
       NetBIOS over Tcpip. . . . . . . . : Enabled

    So, it says my DHCP server is my VPN device (I have access to it, DHCP is enabled).

    I have a domain controller here with IP 10.196.24.31 that's why the DNS points to it.

    Some computers just can't get IP address, they keep getting 169 IPs.

    I restarted my Juniper device and some times the computers work, but during the day if some one turn on a "new" computer it doesn't get IP anymore. I feel like I have a limited number of IPs then after filled the DHCP doesn't give an IP anymore. I have a restriction on DHCP to give only numbers from 10.196.24.51~220 but I did a scan here and there's a lot of IPs between 51 and 220 available. So I don't know what's happening.

    I beg you to help me I am out of options.


    Kind regards.

    Monday, May 15, 2017 6:24 PM

All replies

  • Hi rdgcatell,

    Apologize for my delayed response.

    >>I have an ISP managed router here

    Did you configure DHCP service in your router? If it is not necessary, you could disable the DHCP service in your router.

    If the DHCP service in your router can not be disabled, you could try the following:

    Please check if the DHCP server in your domain is the authorized one.

    If not, please authorize it.

    For your reference:

    Authorize a DHCP Server in AD DS

    https://technet.microsoft.com/en-us/library/dd183580(v=ws.10).aspx

    Best Regards,

    Candy



    Please remember to mark the replies as answers if they help.
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    Thursday, May 25, 2017 8:13 AM
  • Hi rdgcatell

    Just checking in to see if the information provided was helpful.

    Please let us know if you would like further assistance.

    Best Regards,

    Candy


    Please remember to mark the replies as answers if they help.
    If you have feedback for TechNet Subscriber Support, contact tnmff@microsoft.com.

    Wednesday, May 31, 2017 7:47 AM