Re: [Lksctp-developers] Inconsistent behavior while sending HEART_BEAT_ACK after primary path recovery in Multi-Homing setup (using RHEL4)

[Vlad Y. <vya...@gm...>]

On 06/14/2012 01:14 PM, Chinmaya Dwibedy wrote:

> 5)    Now the packets from peer to host are transmitted over primary path but the packets from host to peer are transmitted over secondary path. After some times, Host sends HEART_BEAT_REQ over primary path by keeping its primary IP (192.168.16.125) as source IP and primary IP of Peer (192.168.16.129) as destination IP. Peer sends back the HEART_BEAT_ACK over primary path by keeping its primary IP (192.168.16.129) as source IP and primary IP of Host (192.168.16.125) as destination IP. Then after all the data packets between host and peer are exchanged in primary path.
> What I understand, the point 4) does not conform to section 3.3.6 of rfc-2960 which says that, “A HEARTBEAT ACK is always sent to the source IP address of the IP datagram containing the HEARTBEAT chunk to which this ACK is responding”. But in the above case, host replies HEART_BEAT_ACK to peer by keeping the destination IP as secondary IP of peer which is different than that has been received as source IP with HEART_BEAT message. It seems to confirm that, it is a bug in kernel.
> I was going thru Linux kernel mailing at vger.kernel.org&   found at http://www.archivum.info/bk-...@vg.../2004-10/00084/(SCTP)-Fix-HEARTBEAT_ACKs-being-sent-to-wrong-dest.-ip-address-in-a.html, that, the patch has been provided to resolve this issue.
> In addition, the link at http://lksctp.sourceforge.net/ChangeLog states that, the same fix has been merged into Linux kernel 2.6.10.I believe, applying the patch on the top of RHEL4 will eliminate this issue. Can anyone please confirm? Thanks in advance for your response.
>
> Regards,
> Chinmaya

Yes, this should fix your problem.

-vlad