Hi Scott, On Fri, 2015-09-11 at 14:06 -0400, Scott L. Lykens wrote: > Hello all - > > I apologize if this is not the proper forum to bring this to - I have > not been able to find any other type of user mailing list which would > be appropriate for such a question. > > I am working on setting up an LIO based FC target for a small cluster > of Hyper-V machines and am having problems with PR support in kernel > 4.2. > > I have two IBLOCK backed LUNs exposed to the FC initiator which is > connecting using MS’s MPIO implementation. Using kernel > 3.19.0-28-generic (Ubuntu 14.04 current) on the target, the hyper-v > cluster will happily connect, validate, and use the target LUNs. The > Validate Cluster report passes the storage section 100% green. > > I’ve had some stability problems with the qla2xxx driver in kernel > 3.19 and so in reading this list it became clear that there are > updates in the current kernel that address stability. I upgraded the > kernel to 4.2 (using exton’s kernel, “compiled the Ubuntu way”) and > tested again. Under 4.2 the cluster won’t attach to the targets unless > they are in maintenance mode on the cluster and Validate Cluster fails > in testing SCSI-3 Persistent Reservations. > > The only difference between these two situations is the kernel - > 3.19.0 versus 4.2.0. > > I am hoping I am just missing setting an attribute or option but I > have not found one which seems to be on point here. > > Any ideas would be appreciated. There where a number of RCU changes that went in during the v4.2 time frame that effect PR code, so I wouldn't be surprised if a regression is lurking.. It would be very helpful to get your target side log while running MSFT validate cluster on both v4.2 and v3.19 kernel code with following enabled: echo 'file target_core_pr.c +p' > /sys/kernel/debug/dynamic_debug/control Note this requires the kernel to be built with CONFIG_DYNAMIC_DEBUG=y, and debugfs is mounted at /sys/kernel/debug. With that information, it should be pretty easy to troubleshoot. Thanks for reporting. --nab -- To unsubscribe from this list: send the line "unsubscribe target-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
