Comment # 4 on bug 923150 from Diego Ercolani

When the problem have began, I noticed that the boot process dropped to rescue
shell, after the generation of a new initrd, now the boot process simply
freezes (almost for 2 hours) trying to launch processes that depend on the disk
it don't find.
So I did this workaround:
- disable mysql & disable bacula-dir service
- added "nofail" attribute to fstab to 
  - /dev/md/mysql
  - /dev/md/ROOTHOME
  - /dev/nonraid/tmp

I rebooted the machine and, as you can see in the movie system boot up and:

- /dev/md/lvm is correctly started
- /dev/raid/mysql, /dev/raid/ROOTHOME, /dev/nonraid/tmp are inactive

So to address:
lvchange -ay /dev/nonraid/tmp
lvchange -ay /dev/raid/mysql
lvchange -ay /dev/raid/ROOTHOME

(systemd mount "new" filesystems authomatically)

rcmysql start
rcbacula-dir start

This should provide another bit of information: http://youtu.be/FzR_V5ULSK0