Nimble storage devices periodically do not form multipath devices

Issue

• After booting, Nimble storage devices are expected to form a multipath device, but when the system fully boots they did not.

Expected:

    NAME                      MAJ:MIN RM   SIZE RO TYPE  MOUNTPOINT
    sda                         8:16   0 745.2G  0 disk  
    |-sda1                      8:17   0     1G  0 part  /boot
    `-sda2                      8:18   0 550.8G  0 part  
      |-rhel-root             253:0    0   293G  0 lvm   /
      `-rhel-swap             253:1    0  62.5G  0 lvm   [SWAP]
    sdb                         8:32   0   7.6T  0 disk  
    `-mpatha                  253:3    0   7.6T  0 mpath 
    sdc                         8:48   0   7.6T  0 disk  
    `-mpatha                  253:3    0   7.6T  0 mpath 

Actual:

    NAME                      MAJ:MIN RM   SIZE RO TYPE  MOUNTPOINT
    sda                         8:16   0 745.2G  0 disk  
    |-sda1                      8:17   0     1G  0 part  /boot
    `-sda2                      8:18   0 550.8G  0 part  
      |-rhel-root             253:0    0   293G  0 lvm   /
      `-rhel-swap             253:1    0  62.5G  0 lvm   [SWAP]
    sdb                         8:32   0   7.6T  0 disk  
    sdc                         8:48   0   7.6T  0 disk  

• Systemd kills either multipathd.service, or lvm2-activation-early.service during the boot process. If multipathd.service is the service that is killed, multipaths will never be formed.

  Feb  3 16:40:11 localhost systemd: Found ordering cycle on lvm2-activation-early.service/start
  Feb  3 16:40:11 localhost systemd: Found dependency on multipathd.service/start
  Feb  3 16:40:11 localhost systemd: Found dependency on nlt.service/start
  Feb  3 16:40:11 localhost systemd: Found dependency on lvm2-monitor.service/start
  Feb  3 16:40:11 localhost systemd: Found dependency on lvm2-activation.service/start
  Feb  3 16:40:11 localhost systemd: Found dependency on lvm2-activation-early.service/start
  Feb  3 16:40:11 localhost systemd: Breaking ordering cycle by deleting job multipathd.service/start
  Feb  3 16:40:11 localhost systemd: Job multipathd.service/start deleted to break ordering cycle starting with lvm2-activation-early.service/start