On 12/12/2016 07:50 PM, Jim Fehlig wrote:
On 12/03/2016 07:09 AM, John Ferlan wrote:
ping?
Sorry, I seem to have lost your initial cover letter so responding here...
On 11/18/2016 09:26 AM, John Ferlan wrote:
https://bugzilla.redhat.com/show_bug.cgi?id=1349696
Lots of details in the bz, but essentially the problem is that providing a "parent" scsi_hostX value has drawbacks on reboots because what was scsi_hostX could turn into scsi_hostY on subsequent reboots.
So add the ability to use the parent wwnn/wwpn or fabric_wwn as 'search' criteria in order to create either non persistent vHBA's via nodedev or persistent vHBA's via storage pools.
I've not looked at all the patches in detail, but I have been giving them a fair bit of testing and haven't noticed any problems thus far.
Thanks - that's good to know...
Once question I do have is related to volume detection in vport-based pools. Currently when there are multiple paths to a LUN only the active ones are displayed in the pool. Inactive paths are ignored since saferead() fails in src/storage/storage_backend.c:virStorageBackendDetectBlockVolFormatFD(). Without the inactive paths, there would be no path to the LUN if it was trespassed. I made the below hack to virStorageBackendUpdateVolTargetInfo() to show the inactive paths too, and was able to pass those to the guest allowing it to handle multipathing. Is there a reason the inactive paths are ignored?
I suppose for NPIV/vHBA LUN's it perhaps makes sense to have inactive paths. Been a while since I went down that path... Seems like virStorageBackendSCSINewLun should be able to receive a -2 in order to ignore VIR_STORAGE_VOL_READ_NOERROR. There's a sequence of changes I made starting with commit id '22346003d' which allow/support a -2 return. Those lead to a linked bz in the commit message describing a problem with multipath device with 'active' and 'ghost' devices. I'd have to dig more on that to jiggle the memory. Perhaps it's a path that needs a bit more code to more properly determine details of the LUN returning -2... IOW: Something that would dig on the failed device to see if it was mpath related. John
Regards, Jim
Index: libvirt-2.5.0/src/storage/storage_backend.c =================================================================== --- libvirt-2.5.0.orig/src/storage/storage_backend.c +++ libvirt-2.5.0/src/storage/storage_backend.c @@ -1941,8 +1941,11 @@ virStorageBackendUpdateVolTargetInfo(vir
if (withBlockVolFormat) { if ((ret = virStorageBackendDetectBlockVolFormatFD(target, fd, - readflags)) < 0) + readflags)) < 0) { + if (ret == -2) + ret = 0; goto cleanup; + } }
cleanup: