From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pradeep Satyanarayana Subject: Re: how to preserve QP over HA events for librdmacm applications Date: Thu, 20 Sep 2012 10:37:52 -0700 Message-ID: <505B5470.9030707@linux.vnet.ibm.com> References: <5059E82E.9020600@mellanox.com> <1828884A29C6694DAF28B7E6B8A8237346A8E418@ORSMSX101.amr.corp.intel.com> <5059EA48.1040407@mellanox.com> <46C75A5F-AD9F-45CF-A441-B7D5F60709D8@ornl.gov> <1828884A29C6694DAF28B7E6B8A8237346A8E47E@ORSMSX101.amr.corp.intel.com> <86756672-ADCC-4EF0-A24C-19C4A0EB8188@ornl.gov> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <86756672-ADCC-4EF0-A24C-19C4A0EB8188-1Heg1YXhbW8@public.gmane.org> Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: "Atchley, Scott" Cc: "Hefty, Sean" , Alex Rosenbaum , Or Gerlitz , "linux-rdma (linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org)" List-Id: linux-rdma@vger.kernel.org On 09/19/2012 11:14 AM, Atchley, Scott wrote: > On Sep 19, 2012, at 1:05 PM, "Hefty, Sean" wrote: > >>> I too would be interested in bringing a QP from error back to a usable state. I >>> have been debating whether to reconnect using the current RDMA calls versus >>> trying to transition the existing RC QP. >>> >>> I assumed to transition the existing QP that I would need to open a socket to >>> coordinate the two sides. Is that correct? >>> >>> If I were instead to use rdma_connect(), does it require a new CM id or just a >>> new QP within the same id? What if you say pre-created a second (fail over) QP for HA purposes all under the covers of a single socket? And both QPs were connected before the failure. Not sure if that would work with the same CM id though. If not, we will need to rdma_connect() the second QP after failure. By having a second QP and bound to say a different port/device, one could survive not just link up/down events, but device failures too. Would that be more generic? Thanks Pradeep -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html