On Fri, 2019-11-22 at 13:27 -0700, Drew Hastings wrote: > My use case doesn't lend itself well to multipathd, so I'm trying to > implement multipathing with device mapper directly. > > My only assumption is that the multipath features, in particular > queue_mode bio, prevent this from behaving properly. If that is the > case, why can this not be achieved with bios, as this is not a > limitation of raid1 (which will load balance read IO to device mapper > targets). I also believe this is the only feature option that is > viable for me, since this multipath device is on top of device mapper > targets. I think you are seeing this FIXME: https://elixir.bootlin.com/linux/v4.19.79/source/drivers/md/dm-mpath.c#L612 For your testing, perhaps you just remove that if(!pgpath) condition. Regards, Martin -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel