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cable modem DHCP with 9.351

Hello everyone.  I am new to this community. 

I just started playing around with the home edition of UTM.  I believe that I have everything set correctly, but it does not seem that the ethernet that I have assigned to WAN is picking up the DHCP assigned address.  The port stays down.

So what I did to ensure that everything is working and I have everything set correctly.  I have a netgear router attached to my cable modem.  From the netgear router LAN port I have going to the Sophos WAN (DHCP).  Everything working great! 

Next test, I gave the WAN (Sophos) a static IP that was assigned from the cable modem and it worked. 

The question, why isn't the cable modem and the WAN communicating correctly?  Is there something else that I missed?

Again running the latest version 9.351, WAN port is set as follow:

NAME: WAN

Type: Ethernet

Hardware: eth0

Dynamic IP:  checked

IPv4 GW: checked



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Parents
  • PREFACE:
    My UTM runs in a VMware virtual machine, which runs on a Mac mini computer. The UTM's internal LAN interface is bridged, and shared with the Mac mini's built-in Ethernet connector. The UTM's external WAN interface is a cheap KDLINKS UN1, a USB 3.0 to gigabit Ethernet adapter.

    DISCUSSION:
    Your problem sounds similar to one that I have been seeing intermittently from my own UTM. Every week I download a large backup file over sftp through the UTM. Four or five times since last July (2015), the connection suddenly dropped, and I was unable to connect to the Internet for several hours. The problem was that the UTM could not get a public Internet IP address from Time Warner Cable (TWC), the Internet Service Provider (ISP).

    The Internet dropout and DHCP problem appeared only during the large file, high speed downloads.

    If I connected a computer or an old router to the cable modem, that device got an IP address. When I connected the UTM, it did not. It showed "0.0.0.0" for IPv4 and "fe80..." for IPv6. I spent a lot of time working with TWC's third tier support, but nothing fixed the problem. They tried multiple different methods to "send hits" to my cable modem. The cable modem is a simple cable to Ethernet bridge, a Motorola SurfBoard SB6141.

    In all cases, it would fix itself after 2-4 hours of downtime. Nothing else I tried worked from either my side or the TWC side. I rebooted everything. (What I may not have done is power-cycled the server that runs the UTM in a virtual machine, and that's important!)

    It happened again about a week ago. I think I found the root cause of the problem. It is just a hypothesis, but the next time it happens, I will know for sure if I am right.

    HYPOTHESIS:
    When put under high communications load (around 100 Mbits/sec) the KDLINKS USB/Ethernet adapter fails. The failure appears as a DHCP client/server problem.

    PROCEDURE (for me):
    1. Disconnect the USB/Ethernet adapter.
    2. Shut down the UTM (via WebAdmin)
    3. Reconnect the USB/Ethernet adapter
    4. Reboot the Mac mini server (which automatically launches the virtual machine UTM).

    My guess is that you may be having similar Ethernet adapter failures in your UTM. I suggest that you shutdown your hardware and let everything cool off. Make sure that the Ethernet adapter or chips are powerless and have a chance to cool down. See if your UTM gets an IP address from the DHCP server. It seemed to work for me last time, and I will know for sure the next time it happens.

    Many people here in the forums recommend genuine Intel or Broadcom Ethernet adapters. They may be right. :-)

    I hope this helps!

Reply
  • PREFACE:
    My UTM runs in a VMware virtual machine, which runs on a Mac mini computer. The UTM's internal LAN interface is bridged, and shared with the Mac mini's built-in Ethernet connector. The UTM's external WAN interface is a cheap KDLINKS UN1, a USB 3.0 to gigabit Ethernet adapter.

    DISCUSSION:
    Your problem sounds similar to one that I have been seeing intermittently from my own UTM. Every week I download a large backup file over sftp through the UTM. Four or five times since last July (2015), the connection suddenly dropped, and I was unable to connect to the Internet for several hours. The problem was that the UTM could not get a public Internet IP address from Time Warner Cable (TWC), the Internet Service Provider (ISP).

    The Internet dropout and DHCP problem appeared only during the large file, high speed downloads.

    If I connected a computer or an old router to the cable modem, that device got an IP address. When I connected the UTM, it did not. It showed "0.0.0.0" for IPv4 and "fe80..." for IPv6. I spent a lot of time working with TWC's third tier support, but nothing fixed the problem. They tried multiple different methods to "send hits" to my cable modem. The cable modem is a simple cable to Ethernet bridge, a Motorola SurfBoard SB6141.

    In all cases, it would fix itself after 2-4 hours of downtime. Nothing else I tried worked from either my side or the TWC side. I rebooted everything. (What I may not have done is power-cycled the server that runs the UTM in a virtual machine, and that's important!)

    It happened again about a week ago. I think I found the root cause of the problem. It is just a hypothesis, but the next time it happens, I will know for sure if I am right.

    HYPOTHESIS:
    When put under high communications load (around 100 Mbits/sec) the KDLINKS USB/Ethernet adapter fails. The failure appears as a DHCP client/server problem.

    PROCEDURE (for me):
    1. Disconnect the USB/Ethernet adapter.
    2. Shut down the UTM (via WebAdmin)
    3. Reconnect the USB/Ethernet adapter
    4. Reboot the Mac mini server (which automatically launches the virtual machine UTM).

    My guess is that you may be having similar Ethernet adapter failures in your UTM. I suggest that you shutdown your hardware and let everything cool off. Make sure that the Ethernet adapter or chips are powerless and have a chance to cool down. See if your UTM gets an IP address from the DHCP server. It seemed to work for me last time, and I will know for sure the next time it happens.

    Many people here in the forums recommend genuine Intel or Broadcom Ethernet adapters. They may be right. :-)

    I hope this helps!

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