I'm trying to get mdadm to assemble an array on some multipath disks at boot. System is a fresh install of stretch. By default it seems the mdadm array auto assembles before the multipath devices are created and thus doesn't use the dm- multi path devices but just the sdx devices, which prevents the multipath devices from ever getting created. Adding the DEVICE lines in mdadm.conf for the /dev/mapper/mpathx devices kind of reverses the problem. Now the multipath devices do get created, but the array(and thus the lvol & filesystem) never gets assembled on boot. In the old init days I'd probably add a script that runs mdadm --assemble and mount at the end of boot, but not sure what the right way to handle this in systemd is. mdadm.conf lines:
DEVICE /dev/mapper/mpathb /dev/mapper/mpathc /dev/mapper/mpathd /dev/mapper/mpathe ARRAY /dev/md/0 devices=/dev/mapper/mpathb,/dev/mapper/mpathc,/dev/mapper/mpathd,/dev/mapper/mpathe metadata=1.2 spares=1 name=tst3:0 UUID=7809f500:667e7a8f:45222d03:7405415b Thoughts or suggestions? Thanks, -Eli
