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On 1/6/20 7:33 AM, Radosław Piliszek wrote:
> Folks, this seems to be about C7, not C8, and
> "neutron_legacy_iptables" does not apply here.
> @Jon - what is the kernel bug you mentioned but never referenced?

There was a previous kernel bug in a Centos kernel that broke DNAT, 
https://bugs.launchpad.net/neutron/+bug/1776778 but don't know if this 
is the same issue.  I would have hoped no one was using that kernel by 
now, and/or it was blacklisted.

-Brian

> pon., 6 sty 2020 o 13:13 Jon Masters <jcm at jonmasters.org> napisał(a):
>>
>> I did specifically check for such a conflict tho before proceeding down the path I went :)
>>
>> --
>> Computer Architect
>>
>>
>>> On Jan 6, 2020, at 03:40, Sean Mooney <smooney at redhat.com> wrote:
>>>
>>> On Mon, 2020-01-06 at 10:11 +0100, Radosław Piliszek wrote:
>>>> If it's RHEL kernel's bug, then Red Hat would likely want to know
>>>> about it (if not knowing already).
>>>> I have my kolla deployment on c7.7 and I don't encounter this issue,
>>>> though there is a pending kernel update so now I'm worried about
>>>> applying it...
>>> it sound more like a confilct between legacy iptables and the new nftables based replacement.
>>> if you mix the two then it will appear as if the rules are installed but only some of the rules will run.
>>> so the container images and the host need to be both configured to use the same versions.
>>>
>>> that said fi you are using centos images on a centos host they should be providing your usnign centos 7 or centos 8 on
>>> both. if you try to use centos 7 image on a centos 8 host or centos 8 images on a centos 7 host it would likely have
>>> issues due to the fact centos 8 uses a differt iptables implemeantion
>>>
>>>>
>>>> -yoctozepto
>>>>
>>>> pon., 6 sty 2020 o 03:34 Jon Masters <jcm at jonmasters.org> napisał(a):
>>>>>
>>>>> There’s no bug ID that I’m aware of. But I’ll go look for one or file one.
>>>>>
>>>>> --
>>>>> Computer Architect
>>>>>
>>>>>
>>>>>> On Jan 5, 2020, at 18:51, Laurent Dumont <laurentfdumont at gmail.com> wrote:
>>>>>
>>>>> 
>>>>> Do you happen to have the bug ID for Centos?
>>>>>
>>>>> On Sun, Jan 5, 2020 at 2:11 PM Jon Masters <jcm at jonmasters.org> wrote:
>>>>>>
>>>>>> This turns out to a not well documented bug in the CentOS7.7 kernel that causes exactly nat rules not to run as I
>>>>>> was seeing. Oh dear god was this nasty as whatever to find and workaround.
>>>>>>
>>>>>> --
>>>>>> Computer Architect
>>>>>>
>>>>>>
>>>>>>> On Jan 4, 2020, at 10:39, Jon Masters <jcm at jonmasters.org> wrote:
>>>>>>>
>>>>>>> Excuse top posting on my phone. Also, yes, the namespaces are as described. It’s just that the (correct) nat
>>>>>>> rules for the qrouter netns are never running, in spite of the two interfaces existing in that ns and correctly
>>>>>>> attached to the vswitch.
>>>>>>>
>>>>>>> --
>>>>>>> Computer Architect
>>>>>>>
>>>>>>>
>>>>>>>>> On Jan 4, 2020, at 07:56, Sean Mooney <smooney at redhat.com> wrote:
>>>>>>>>>
>>>>>>>>> On Sat, 2020-01-04 at 10:46 +0100, Slawek Kaplonski wrote:
>>>>>>>>> Hi,
>>>>>>>>>
>>>>>>>>> Is this qrouter namespace created with all those rules in container or in the host directly?
>>>>>>>>> Do You have qr-xxx and qg-xxx ports from br-int in this qrouter namespace?
>>>>>>>>
>>>>>>>> in kolla the l3 agent should be running with net=host so the container should be useing the hosts
>>>>>>>> root namespace  and it will create network namespaces as needed for the different routers.
>>>>>>>>
>>>>>>>> the ip table rules should be in the router sub namespaces.
>>>>>>>>
>>>>>>>>>
>>>>>>>>>>> On 4 Jan 2020, at 05:44, Jon Masters <jcm at jonmasters.org> wrote:
>>>>>>>>>>
>>>>>>>>>> Hi there,
>>>>>>>>>>
>>>>>>>>>> I've got a weird problem with the neutron-l3-agent container on my deployment. It comes up, sets up the
>>>>>>>>>> iptables
>>>>>>>>>> rules in the qrouter namespace (and I can see these using "ip netns...") but traffic isn't having DNAT or
>>>>>>>>>> SNAT
>>>>>>>>>> applied. What's most strange is that manually adding a LOG jump target to the iptables nat PRE/POSTROUTING
>>>>>>>>>> chains
>>>>>>>>>> (after enabling nf logging sent to the host kernel, confirmed that works) doesn't result in any log
>>>>>>>>>> entries. It's as
>>>>>>>>>> if the nat table isn't being applied at all for any packets traversing the qrouter namespace. This is
>>>>>>>>>> driving me
>>>>>>>>>> crazy :)
>>>>>>>>>>
>>>>>>>>>> Anyone got some quick suggestions? (assume I tried the obvious stuff).
>>>>>>>>>>
>>>>>>>>>> Jon.
>>>>>>>>>>
>>>>>>>>>> --
>>>>>>>>>> Computer Architect
>>>>>>>>>
>>>>>>>>> —
>>>>>>>>> Slawek Kaplonski
>>>>>>>>> Senior software engineer
>>>>>>>>> Red Hat
>>>>>>>>>
>>>>>>>>>
>>>>
>>>>
>>>
>