Re: Multi-homing question

[Vlad Yasevich <vyasevich@gmail.com>]

On 11/06/2013 10:45 PM, tsoi andrew wrote:
> Dear Neil,
>
> Attached file is our tcpdump.
> Now our secondary IP doesn't work.
> Please advise. Thanks.
>
> IP info:
> lksctp primary IP is 172.28.129.49
> lksctp secondary IP is 172.28.129.176
>
> Client IP is 10.82.29.240/10.82.29.241
>
>

Since it appears that you are using multiple interfaces
in the same subnet, can you please make sure that:
1) you have arp_ignore set correctly.
2) you have route rules that specify that different source
addresses should be used for different destinations.

Without this, linux will just pick the first/best address
and interface to use and you will not have real multi-homing.

You alternative of course is to set up secondary ip in a different
subnet.  This way you would have more appropriate multi-homing
configuration.

-vlad


>
>
>
> Regards,
> Andrew
>
> On Thu, Nov 7, 2013 at 10:43 AM, tsoi andrew <tsoiandrew@gmail.com> wrote:
>>   Dear Neil,
>>
>> For more information, our secondary IP doesn't response COOKIE_ECHO
>> also. Only our primary IP can response COOKIE_ECHO with COOKIE_ACK.
>>
>> Regards,
>> Andrew
>>
>> On Thu, Nov 7, 2013 at 10:36 AM, tsoi andrew <tsoiandrew@gmail.com> wrote:
>>> Dear Neil,
>>>
>>> Please find my network diagram first.
>>> Now at server side, can't see our lksctp client 4 connection but only
>>> 2 2 connection.  The reason is that heartbeat ACK not found.
>>>
>>> Regards,
>>> Andrew
>>>
>>> On Mon, Nov 4, 2013 at 8:09 PM, Neil Horman <nhorman@tuxdriver.com> wrote:
>>>> On Mon, Nov 04, 2013 at 09:59:44AM +0800, tsoi andrew wrote:
>>>>> Dear Sir,
>>>>>
>>>>> I got a problem when set multi-homing to active/active.
>>>>> That mean, It is expected that our lksctp server have 2 IP to connect
>>>>> 2 IP of destination client with total 4 connections.
>>>>> The flow is that client send "INIT" message with 2 (primary and
>>>>> secondary) IP to our server and lksctp server return INIT_ACK. But
>>>>> when second client send 'heartbeat' to us, lksctp server cannot return
>>>>> ACK.
>>>>> Moreover, we already proved our connectivity correct because when our
>>>>> lksctp server send heartbeat to both destination client and they can
>>>>> return ACK.
>>>>> Would you mind sharing if lksctp lib already configure those
>>>>> multi-homing purpose.
>>>>>
>>>> Can you provide a network diagram and a tcpdump of your connection?
>>>> Neil
>>>>
>>>>>
>>>>>
>>>>> Best Regards,
>>>>> Andrew Tsoi
>>>>> --
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