[ovs-discuss] Warning logs flooding: failed to flow_del (No such file or directory)

[Han Zhou]

That's helpful. But after deleting the more inclusive flow I still
cannot delete the "zombie" flow. It might be there are still more
overlapping flows.
So, I tried ovs-dpctl del-flows, and all the "zombie" flows are gone :)

On Wed, Jul 2, 2014 at 10:28 PM, Alex Wang <alexw at nicira.com> wrote:
> The tcp field is missing, could you try 'ovs-dpctl dump-flow -m' to get
> all fields.  And use it as input to 'ovsdpctl flow-del'
>
> Thanks,
> Alex Wang,
>
>
> On Wed, Jul 2, 2014 at 1:22 AM, Han Zhou <zhouhan at gmail.com> wrote:
>>
>> Hi Alex,
>>
>> On Wed, Jul 2, 2014 at 2:30 PM, Alex Wang <alexw at nicira.com> wrote:
>> >
>> >
>> >
>> > On Tue, Jul 1, 2014 at 7:38 PM, Han Zhou <zhouhan at gmail.com> wrote:
>> >>
>> >> Hi Alex,
>> >>
>> >> That's cool!
>> >> Just one more question.
>> >> >    Due to the race condition in userspace, there is chance that two
>> >> >    overlapping megaflows could be installed in datapath.  And this
>> >> >    causes userspace unable to delete the less inclusive megaflow flow
>> >> >    even after it timeout, since the flow_del logic will stop at the
>> >> >    first match of masked flow.
>> >>
>> >> Does it mean if the more inclusive megaflow (say A) is deleted, then
>> >> the less inclusive megaflow (say B) can be deleted? If so, I can have
>> >> a workaround without updating OVS version: I can find out the more
>> >> inclusive megaflow and manually delete flows with ovs-dpctl in order
>> >> (A -> B), then warning logs should stop, right?
>> >
>> >
>> > Right.  Note you should prevent the relevant traffic from installing the
>> > 'more inclusive' flow between deletions.
>> >
>>
>> I did find out a more inclusive mega-flow, but failed when trying to
>> delete that one:
>> # ovs-dpctl del-flow system at ovs-system
>>
>> "skb_priority(0),in_port(2),eth(src=30:f7:0d:9b:64:41,dst=78:45:c4:fb:c2:2f),eth_type(0x0800),ipv4(src=10.120.139.226/0.0.0.0,dst=10.120.116.69/0.0.0.0,proto=6/0,tos=0/0,ttl=61/0,frag=no/0xff)"
>> 2014-07-02T08:16:29Z|00001|dpif|WARN|system at ovs-system: failed to
>> flow_del (Invalid argument)
>>
>> skb_priority(0),in_port(2),eth(src=30:f7:0d:9b:64:41,dst=78:45:c4:fb:c2:2f),eth_type(0x0800),ipv4(src=10.120.139.226,dst=10.120.116.69,proto=6,tos=0,ttl=61,frag=no)
>> ovs-dpctl: deleting flow (Invalid argument)
>>
>> The error is now "Invalid argument". So what's wrong here?
>>
>> Best regards,
>> Han
>
>