Server Received INIT But give no reponse

[bigstar119]

on my server when client send the package in sctp_init_error.pcap.zip, server give no response. in normal mode server shoud give init_ack response. but it is not ,why?

sctp_init_error.pcap.zip

lksctp version:
lksctp-tools-1.0.17-2.el7.x86_64

sctp_darn -H 10.61.56.136 -P 8014 -l
netstat -an|grep sctp
sctp 10.61.56.136:8014 LISTEN

the network is ok too !!

how can i open the debug log of lksctp-tools and found the problem of it

[lxin]

I don't think there's a debug log that can help with this, as all the handshake of SCTP happens in the kernel.
The INIT packet might be dropped in SCTP rcv path in the kernel, it's likely because of the SCTP checksum.

Please try disabling the SCTP checksum on the server by:

modprobe sctp no_checksums=1

before starting any SCTP programs.

Thanks.

[bigstar119]

@lxin thanks for your advice , i use the pcap4j regenerate the sctp checksum and check it. i Got the same result as you say. the hardward firewall change the checksum in the Network transmission process. when the firewall change the policy everything going fine.
this is not a bug so you can close the issue, thanks!