From amit.bhayani at gmail.com Thu May 5 11:50:30 2016 From: amit.bhayani at gmail.com (Amit Bhayani) Date: Thu, 5 May 2016 17:20:30 +0530 Subject: [sctp-dev] Socket Option SCTP_MAXSEG Message-ID: Hi Guys, I am using lksctp with JDK 7 on top. I was looking for SctpScoketOption to set SCTP_MAXSEG, but didn't find it available. https://docs.oracle.com/javase/7/docs/jre/api/nio/sctp/spec/com/sun/nio/sctp/SctpChannel.html What is best way to restrict the max DATA chunk size for SCTP? Thanks for your help. Amit. -------------- next part -------------- An HTML attachment was scrubbed... URL: From chris.hegarty at oracle.com Thu May 5 13:58:10 2016 From: chris.hegarty at oracle.com (Chris Hegarty) Date: Thu, 5 May 2016 14:58:10 +0100 Subject: [sctp-dev] Socket Option SCTP_MAXSEG In-Reply-To: References: Message-ID: <6BACB680-E1F9-448E-9749-E43D7C8A311F@oracle.com> On 5 May 2016, at 12:50, Amit Bhayani wrote: > Hi Guys, > > I am using lksctp with JDK 7 on top. I was looking for SctpScoketOption to set SCTP_MAXSEG, but didn't find it available. This option is currently not supported. There is an issue tracking adding additional options: https://bugs.openjdk.java.net/browse/JDK-8146626 -Chris. From amit.bhayani at gmail.com Thu May 26 04:19:08 2016 From: amit.bhayani at gmail.com (Amit Bhayani) Date: Thu, 26 May 2016 09:49:08 +0530 Subject: [sctp-dev] Socket Option SCTP_MAXSEG In-Reply-To: <6BACB680-E1F9-448E-9749-E43D7C8A311F@oracle.com> References: <6BACB680-E1F9-448E-9749-E43D7C8A311F@oracle.com> Message-ID: Thanks Chris, Is there way to set this at OS level? The provider is not accepting any packets greater that 1420 Bytes and lksctp keeps doing re-transmission which obviously keeps failing. An finally the link goes down (Abort) Thanks and Regards, Amit. On Thu, May 5, 2016 at 7:28 PM, Chris Hegarty wrote: > > On 5 May 2016, at 12:50, Amit Bhayani wrote: > > > Hi Guys, > > > > I am using lksctp with JDK 7 on top. I was looking for SctpScoketOption > to set SCTP_MAXSEG, but didn't find it available. > > This option is currently not supported. There is an issue tracking adding > additional options: > https://bugs.openjdk.java.net/browse/JDK-8146626 > > -Chris. -------------- next part -------------- An HTML attachment was scrubbed... URL: From chris.hegarty at oracle.com Thu May 26 11:40:46 2016 From: chris.hegarty at oracle.com (Chris Hegarty) Date: Thu, 26 May 2016 12:40:46 +0100 Subject: [sctp-dev] Socket Option SCTP_MAXSEG In-Reply-To: References: <6BACB680-E1F9-448E-9749-E43D7C8A311F@oracle.com> Message-ID: > On 26 May 2016, at 05:19, Amit Bhayani wrote: > > Thanks Chris, > > Is there way to set this at OS level? Looking at the documentation I don?t see any way to do this at the system level. Someone on the lksctp mailing list [1] [2] might know better. > The provider is not accepting any packets greater that 1420 Bytes This seems strange, the SCTP documentation [3] seems at odds with this: "An SCTP receiver MUST be able to receive a minimum of 1500 bytes in one SCTP packet. This means that an SCTP endpoint MUST NOT indicate less than 1500 bytes in its initial a_rwnd sent in the INIT or INIT ACK." I assume you are trying to set SCTP_MAXSEG as a workaround to the issue ( on the receiver side ), rather than attempting to resolve it there? > and lksctp keeps doing re-transmission which obviously keeps failing. An finally the link goes down (Abort) So this looks like a native issue on the receiver side to me, but I do understand your request for SCTP_MAXSEG support at the Java level. Have you confirmed, through a native app, that this resolves the issue you are seeing? I think it would be really useful to bring this up on the lksctp mailing list [2]. If you do, can you please include me. I am interested in the outcome. > > Thanks and Regards, > Amit. -Chris. [1] linux-sctp at vger.kernel.org [2] http://lksctp.sourceforge.net [3] https://tools.ietf.org/html/rfc4960#section-6 > On Thu, May 5, 2016 at 7:28 PM, Chris Hegarty wrote: > > On 5 May 2016, at 12:50, Amit Bhayani wrote: > > > Hi Guys, > > > > I am using lksctp with JDK 7 on top. I was looking for SctpScoketOption to set SCTP_MAXSEG, but didn't find it available. > > This option is currently not supported. There is an issue tracking adding > additional options: > https://bugs.openjdk.java.net/browse/JDK-8146626 > > -Chris. > From amit.bhayani at gmail.com Fri May 27 14:11:33 2016 From: amit.bhayani at gmail.com (Amit Bhayani) Date: Fri, 27 May 2016 19:41:33 +0530 Subject: [sctp-dev] Socket Option SCTP_MAXSEG In-Reply-To: References: <6BACB680-E1F9-448E-9749-E43D7C8A311F@oracle.com> Message-ID: Hi Chris, Thanks for your response. My comments in-line On Thu, May 26, 2016 at 5:10 PM, Chris Hegarty wrote: > > > On 26 May 2016, at 05:19, Amit Bhayani wrote: > > > > Thanks Chris, > > > > Is there way to set this at OS level? > > Looking at the documentation I don?t see any way to do this at the system > level. Someone on the lksctp mailing list [1] [2] might know better. > Let me ask same in lksctp mailing list too. > > > The provider is not accepting any packets greater that 1420 Bytes > > This seems strange, the SCTP documentation [3] seems at odds with this: > > "An SCTP receiver MUST be able to receive a minimum of 1500 bytes in > one SCTP packet. This means that an SCTP endpoint MUST NOT indicate > less than 1500 bytes in its initial a_rwnd sent in the INIT or INIT > ACK." > > I assume you are trying to set SCTP_MAXSEG as a workaround to the > issue ( on the receiver side ), rather than attempting to resolve it there? > Indeed strange. Well the point is not to control the SCTP packet size but full size of IP packet. I mean in single IP packet there can be multiple SCTP packets. I realized that there is VPN between server and client and I believe this VPN is not taking IP packets greater than 1420 Bytes. > > > and lksctp keeps doing re-transmission which obviously keeps failing. An > finally the link goes down (Abort) > > So this looks like a native issue on the receiver side to me, but I do > understand your request for SCTP_MAXSEG support at the Java > level. Have you confirmed, through a native app, that this resolves > the issue you are seeing? > > Now I wonder if I should really try to control the SCTP_MAXSEG or Path MTU. Is there way to hardcode Path MTU in lksctp? > I think it would be really useful to bring this up on the lksctp mailing > list [2]. If you do, can you please include me. I am interested in the > outcome. > > Sure thing. Opening new thread there. > > > > Thanks and Regards, > > Amit. > > -Chris. > > [1] linux-sctp at vger.kernel.org > [2] http://lksctp.sourceforge.net > [3] https://tools.ietf.org/html/rfc4960#section-6 > > > On Thu, May 5, 2016 at 7:28 PM, Chris Hegarty > wrote: > > > > On 5 May 2016, at 12:50, Amit Bhayani wrote: > > > > > Hi Guys, > > > > > > I am using lksctp with JDK 7 on top. I was looking for > SctpScoketOption to set SCTP_MAXSEG, but didn't find it available. > > > > This option is currently not supported. There is an issue tracking adding > > additional options: > > https://bugs.openjdk.java.net/browse/JDK-8146626 > > > > -Chris. > > > > -------------- next part -------------- An HTML attachment was scrubbed... URL: