Re: Possible networking regression in 3.6.0

Chris Clayton
2012-10-01T15:13:05Z

On 10/01/12 10:15, Eric Dumazet wrote:
> On Mon, 2012-10-01 at 09:36 +0100, Chris Clayton wrote:
>>
>
>> 0 ICMP messages received
>> 0 input ICMP message failed.
>> ICMP input histogram:
>> 0 ICMP messages sent
>> 0 ICMP messages failed
>> ICMP output histogram:
>
>>
>> After:
>>
>> $ netstat -s
>> Icmp:
>> 4 ICMP messages received
>> 4 input ICMP message failed.
>> ICMP input histogram:
>> echo replies: 4
>
> So icmp replies come back and are delivered to host instead of being
> forwarded.
>
> I wonder if MASQUERADE broke...
>
> Could you send
>
> iptables -t -nat -nvL

$ iptables -t -nat -nvL
iptables v1.4.15: can't initialize iptables table `-nat': Table does not
exist (do you need to insmod?)
Perhaps iptables or your kernel needs to be upgraded.

> conntrack -L # while ping is running from guest

$ conntrack -L
conntrack v1.2.2 (conntrack-tools): Operation failed: invalid parameters

Forgive me for asking, but why is the problem not down to the change
that I identified by bisecting? The title of the patch is "ipv4: Cache
local output routes" and, although I'm a million miles from being an
expert here, to me it does make it look a good candidate.
http://marc.info/?l=linux-netdev&m=134797809611847&w=2

>
>
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