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Forum Discussion

DougB628's avatar
DougB628
Apprentice
Jan 25, 2019

DHCP not working properly, log filling with DHCP assignments

So I have noticed that after rebooting, sometimes DHCP doesn't work properly. No devices that use DHCP, whether they have a DHCP reservation or not, get DHCP assigned IP addresses. Whenever this prob...
Troubleshooting
ekhalil's avatar
ekhalil
Master
Jan 28, 2019
DougB628 wrote:

...........

To me, it seems that the problem lies in the DHCP Offer packet sent in response to the DHCP Discover packet from the client. The client, for whatever reason, either doesn't get the DHCP Offer packet, or can't read it properly.

..........

DougB628 Thanks for doing a thourough troubleshooting anf for the good analysis.

I'd look at this differently. I think that the fact that Orbi does not reply to the DHCP Discover packets makes me think that those packets were really sent to another element in the network. Does the ISP modem/router provide any routing functionality? Do you have any other network elements (like extenders, repeaters, ...) that can supply DHCP functionality that can cause such an issue?

DougB628's avatar
DougB628
Apprentice
Jan 28, 2019

My cable modem is an Arris Surfboard. I purchased it myself from Amazon, it was not provided by my ISP. It definitely has no DHCP functionality. No other devices on the network that can provide DHCP, at least not that is enabled. The other indication that it is the Orbi's problem is that it resolves itself after resetting DHCP a few times. Sometimes only one reset (turn off DHCP, apply, turn on DHCP, apply) is needed, other times it's two, three, or four times. Once it stablizes, it's 100% good for quite a while. I'm still learning what changes I make can trigger at least partial resets of things, and there are definitely things that appear to reset DHCP (I see my phone lose its wifi in these cases), and then it's a crap shoot as to whether it will come back stable or not. So I've definitely learned to leave everything alone if its working. I need to build trust back up from my wife - at this point she thinks either that I just want to play with it, and don't give a damn how it affects everyone, or that I truly have no clue what I'm doing. I know the first one is not right... jury is still out on the second...

  • FURRYe38's avatar
    FURRYe38
    Guru - Experienced User
    Jan 28, 2019

    What is the Mfr and model# of the ethernet switches are you using in the configuration?

    DougB628 wrote:

    My cable modem is an Arris Surfboard. I purchased it myself from Amazon, it was not provided by my ISP. It definitely has no DHCP functionality. No other devices on the network that can provide DHCP, at least not that is enabled. The other indication that it is the Orbi's problem is that it resolves itself after resetting DHCP a few times. Sometimes only one reset (turn off DHCP, apply, turn on DHCP, apply) is needed, other times it's two, three, or four times. Once it stablizes, it's 100% good for quite a while. I'm still learning what changes I make can trigger at least partial resets of things, and there are definitely things that appear to reset DHCP (I see my phone lose its wifi in these cases), and then it's a crap shoot as to whether it will come back stable or not. So I've definitely learned to leave everything alone if its working. I need to build trust back up from my wife - at this point she thinks either that I just want to play with it, and don't give a damn how it affects everyone, or that I truly have no clue what I'm doing. I know the first one is not right... jury is still out on the second...