On Wed, 23 Nov 2011 10:12:37 -0800 Hal Rosenstock <hal.rosenst...@gmail.com> wrote:
> > > On Wed, Nov 23, 2011 at 1:08 PM, Ira Weiny > <wei...@llnl.gov<mailto:wei...@llnl.gov>> wrote: > On Tue, 22 Nov 2011 06:17:00 -0800 > "d...@celticblues.com<mailto:d...@celticblues.com>" > <d...@celticblues.com<mailto:d...@celticblues.com>> wrote: > > > Where can I find out more on how to do this, i.e. use opensm to create > > mc groups at startup? > > This is not in an official release yet. But if you are willing, you can get > the latest opensm code here: > git://git.openfabrics.org/~alexnetes/opensm.git<http://git.openfabrics.org/~alexnetes/opensm.git> > > Build it and check out the man page on how to configure your partition config > file. > > Let me know if the man page is insufficient documentation. > > FWIW - Yes but this only solves #1 and not #2 so is this really useful here ? > The problem doesn't seem to be creation of MC group but rather using the RDMA > CM APIs for this. > Your right this does not solve his problem directly. But I figured I would chime in since someone is likely to run across this thread and wonder the same thing should they want OpenSM to create MC groups. :-) Sorry if I have derailed the conversation too far. Ira > -- Hal > > > Ira > > > > > > > Quoting Ira Weiny <wei...@llnl.gov<mailto:wei...@llnl.gov>>: > > > > > On Mon, 21 Nov 2011 09:05:22 -0800 > > > "Hefty, Sean" <sean.he...@intel.com<mailto:sean.he...@intel.com>> wrote: > > > > > >> > From what I understand, and I may not understand correctly, to > > >> > perform IB Multicast, betweeen two nodes, I need to swap addresses and > > >> > remote keys for the two nodes. In the examples I have seen this has > > >> > > >> You only need to do this for unicast UD. Multicast doesn't require > > >> exchanging addresses and qkeys, but see below. > > >> > > >> > been done via RDMA CM directly between the two nodes. Does it matter > > >> > how this information is exchanged? In my application I will have > > >> > > >> For multicast, you need to 1. have the SA create the multicast > > >> group and 2. join the group. To create the group, you need to > > >> either have the SA automatically create the group (if this is > > >> possible) or create it dynamically. To create the group > > >> dynamically from user space, you should use the rdma_cm or ib_umad > > >> interfaces. The rdma_cm is easier. > > >> > > > > > > FWIW, OpenSM (current master branch) now has the ability to create > > > multicast groups at startup, so 1 is possible. > > > > > > See: http://www.spinics.net/lists/linux-rdma/msg10021.html > > > > > > Ira > > > > > >> To join the group, you need to let the SA know that the node should > > >> receive multicast traffic, so that it can program the switches. > > >> This is done through the rdma_cm (easy way) or using ib_umad (hard > > >> way that gets harder if you want to support multiple applications > > >> joining the same group from the same system). > > >> > > >> > several nodes multicasting to several other nodes and I want to manage > > >> > the connections from a independent application. What I would like to > > >> > do is write this application, server, etc. so that each node would > > >> > request connection with another node and then be provied with the > > >> > information it needs to multicast. For example... Node 1 would > > >> > request a connection (from the server app) Node 2 and Node 2 would > > >> > request a connection (again, from the server app) to Node 1. The > > >> > Server app would provide Node 2's "credentials" to Node 1 and likewise > > >> > to Node 2. Is this even possible? > > >> > > >> The SA basically does the work that you're describing for your > > >> server app. Node 1 can ask the SA to create a multicast group. > > >> Node 2 can ask to join that group. Somehow node 2 needs to know > > >> what group node 1 created. > > >> -- > > >> To unsubscribe from this list: send the line "unsubscribe linux-rdma" in > > >> the body of a message to > > >> majord...@vger.kernel.org<mailto:majord...@vger.kernel.org> > > >> More majordomo info at http://vger.kernel.org/majordomo-info.html > > > > > > > > > -- > > > Ira Weiny > > > Member of Technical Staff > > > Lawrence Livermore National Lab > > > 925-423-8008<tel:925-423-8008> > > > wei...@llnl.gov<mailto:wei...@llnl.gov> > > > > > > > > > > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-rdma" in > > the body of a message to > > majord...@vger.kernel.org<mailto:majord...@vger.kernel.org> > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > > -- > Ira Weiny > Member of Technical Staff > Lawrence Livermore National Lab > 925-423-8008<tel:925-423-8008> > wei...@llnl.gov<mailto:wei...@llnl.gov> > -- > To unsubscribe from this list: send the line "unsubscribe linux-rdma" in > the body of a message to > majord...@vger.kernel.org<mailto:majord...@vger.kernel.org> > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- Ira Weiny Math Programmer/Computer Scientist Lawrence Livermore National Lab 925-423-8008 wei...@llnl.gov -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
