Bug#804629: linux-image-amd64: Cannot mount LVM RAID1 file system at boot

[SW Riccardo Scartozzi]

I was experiencing the same issue as describe in this bug report and, as 
pointed by Harrison Metzger, the bug was probably introduced after 
kernel 3.16-3-amd64 because for sure it was working until that version.

I don't get what causes the problem. It could be interesting to test if 
the problem is affect only if the mirror is a type raid1 or also if it 
is a type "mirror" (legacy). I don't know neighter if there is a problem 
while shutting down (is it the same if the OS reboot or it before 
rebooting the mirror is deactivate?).

But the funniest thing is that if you activate lvmetad (switch to option 
"use_lvmetad = 1" in /etc/lvm/lvm.conf) the lvm with mirror type as 
raid1 starts to work again after reboot (at least tested on squeeze 
Linux 4.9.0-0.bpo.2-amd64 #1 SMP Debian 4.9.13-1~bpo8+1 (2017-02-27) 
x86_64 GNU/Linux). I don't know why nor it seem documented. Hope that 
this will save some headache to you as well.

Cheers,

risca