[Lksctp-developers] SCTP NAT'ing not working

[Gupta Nitin-A. <nit...@mo...>]

We have trying the following scenario to setup multihome endpoint.
 
A [client] connects to B using IP4.
B [server] sends the IP4/ IP3 as the multihome IPs.
A tries to heartbeat on IPs it received from server [IP4/ IP3]
At this junture, HB to IP4 works as its direct route. but HB to IP3 is
being rejected [ABORT] by B.
 
       Why is NAT'ing not working in this case on host C?
 
NOTE -Observed that NAT'ing works on host C if we try connecting the
client 
to using IP2 as destination but not when only HB arrives at host C.
 
The setup configuration is as following,
            
                /--------------------- [IP4] B
A [IP1] ---
                \ [IP2] C [IP3'] --- [IP3] B
Host C has the routing rule to forward any sctp packets received at IP2
forward to IP3
PREROUTING 1 -j DNAT -d IP2 -p sctp --to-destination IP3
NOTE - including port in rule also didn't help.
 
Is there anything we may be missing in our config for multihome. Any
suggestions are appriciated.
 
read about alias sctp patch on google to enhance NAT'ing for SCTP is
that needed here ?