[ovs-dev] [PATCH ovn] Support configuring Load Balancer hairpin source IP.

[Dumitru Ceara]

On 2/3/21 3:26 PM, Numan Siddique wrote:
> On Fri, Jan 15, 2021 at 11:56 PM Dumitru Ceara <dceara at redhat.com> wrote:
>>
>> In case traffic that gets load balanced is DNAT-ed to a backend IP that
>> happens to be the source of the traffic then OVN performs an additional
>> SNAT to ensure that return traffic is directed through OVN.
>>
>> Until now the load balancer VIP was chosen as SNAT IP.  However, in
>> specific scenarios, the CMS may prefer a different IP, e.g., a single
>> cluster-wide IP.  This commit adds support, through the newly added
>> Load_Balancer.option 'hairpin_snat_ip', to allow the CMS to explicitly
>> chose a SNAT IP.
>>
>> Due to the fact that now traffic that was hairpinned might need to be
>> SNAT-ed to different IPs for different load balancers that share the
>> same VIP address value we need to also explicitly match on L4 protocol
>> and ports in the 'OFTABLE_CT_SNAT_FOR_VIP' table.
>>
>> Signed-off-by: Dumitru Ceara <dceara at redhat.com>
> 
> Thanks Dumitru for this patch. The patch LGTM.
> 
> I applied to the master branch.
> 
> Numan
> 

Thanks!