A bug in IPv6 DHCP server

Initially I was planning on reporting this in v19.0.1 forum but as the the issue is still present in v19.5 EAP here is a good as place as any.

I have a static IPv6 address assigned to a W10 PC. 

The VM running v7.3d also picks up the same IPv6 address.

I have edited the VM network and it is assigned its own static IPv6 address which is picks up as well as the w10 PCs IPv6 address.

Ian

  • @rfcat_vk Could you provide some snapshots of what you are seeing, you mention static addresses on your W10PC and then a static IPv6 address on your VM network, but mention DHCP in the post title.  Is DHCP handing out duplicate IP addresses, or is DHCP handing out an address you have already manually configured on a VM?  Because that is normal, albeit an issue with DHCP on any system. IP addresses statically assigned must be outside the range of DHCP scopes.  Maybe i misread the post, but may be able to help if i understand more clearly.

  • Not the same issue, but I've noticed something a bit odd IPv6-DHCP-wise: I was running IPv6 via a 6in4 tunnel to HE, but decided it might be causing some issues so shut it down. (By which I mean shut down the tunnel, the gateway, the DHCPv6, the RA's -- everything associated with IPv6.)

    But I'm seeing devices that have IPv6 addresses that I was assigning via DHCPv6 and it appears that they've been renewed recently. (I shut down IPv6 a month or two ago.) So I almost suspect that DHCPv6 is still running (after reboots of devices and the XGS87) or something weird.

    [Clarified what I meant by "shutdown" and "reboot".]

  • I use static addresses assigned in the DHCP server, outside the scope range. The w10pc picks up its ipv6 address at boot time, the VM server also uses DHCP to receive an address from within the scope, but picks up the one already assigned to the w10pc outside the scope. When I assign an address to the VM as in fixed within the VM, but use DHCP to pickup network details the VM receives the address assigned to it plus the one assigned to the w10pc.

    I hope that clarifies the issue.

    Wayne, you would need to disable ipv6 on the interface based on current behaviour of the ipv6 DHCP server.

    Ian

    XG115W - v20 GA - Home

    XG on VM 8 - v20 GA

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  • My apologies, my brain was not fully engaged before starting this thread. I should have tried using a different network which I will do shortly.

    Ian

    XG115W - v20 GA - Home

    XG on VM 8 - v20 GA

    If a post solves your question please use the 'Verify Answer' button.

  • Move to another network and the issue does not appear.

    So, more work required on investigating why this happens on one network and not another. Maybe because this network does not have any static ip addresses.

    Ian

    XG115W - v20 GA - Home

    XG on VM 8 - v20 GA

    If a post solves your question please use the 'Verify Answer' button.

  • Hi folks,

    issue resolved very strange way, a restart of the management console, not a restart of the entire vm box. Strange.

    ianf

    XG115W - v20 GA - Home

    XG on VM 8 - v20 GA

    If a post solves your question please use the 'Verify Answer' button.