Convert LVM to LVM RAID1 - mdadm

[shockwavecs]

I am having trouble converting my existing LVM to LVM+RAID1.
I have used the following tutorials in order to help me along. Unfortunately I hit a wall on step 18 of link 2.

Link 1:
Google this: How To Set Up Software RAID1 On A Running System (Incl. GRUB Configuration) (Fedora | HowtoForge - Linux Howtos and Tutorials

Link 2:
Google this: LVM Single Drive to LVM RAID 1 Mirror Migration - Spiceworks

I get it to mirror the boot partition under /dev/md0:

[root ~]# cat /proc/mdstat 
Personalities : [raid1] 
md1 : active raid1 hdc2[1]
      976655488 blocks [2/1] [_U]
      
md0 : active raid1 hdc1[1] hdb1[0]
      104320 blocks [2/2] [UU]

but step 18 shows:

[root ~]# pvcreate -v /dev/md1
    Wiping cache of LVM-capable devices
    Wiping internal VG cache
    Device /dev/md1 not found (or ignored by filtering).

mdadm --detail --scan shows the following:

[root ~]# mdadm --detail --scan
ARRAY /dev/md0 level=raid1 num-devices=2 metadata=0.90 UUID=dc49ac1e:5f331bfd:f1220ec9:d6d944a0
ARRAY /dev/md1 level=raid1 num-devices=2 metadata=0.90 UUID=25323f02:d5fe868c:22f7455f:ed368c09

my drive layout right now:

[root ~]# fdisk -l | grep hd
Disk /dev/hdb: 1000.2 GB, 1000204886016 bytes
/dev/hdb1   *           1          13      104391   fd  Linux raid autodetect
/dev/hdb2              14      121601   976655610   8e  Linux LVM
Disk /dev/hdc: 1000.2 GB, 1000204886016 bytes
/dev/hdc1               1          13      104391   fd  Linux raid autodetect
/dev/hdc2              14      121601   976655610   fd  Linux raid autodetect

Any ideas why I would not be able to pvcreate?

I can output any information related to this setup if you would like.


edit:

just did this:

[root@stlnas1 ~]# mdadm --examine /dev/md1
mdadm: No md superblock detected on /dev/md1.

is this why?

[shockwavecs]

i started the whole process over and I am STILL stuck. pvcreate fails. i dont know why.

[shockwavecs]

i had to do the following:

vim /etc/lvm/lvm,conf

edit the filter section:

filter = [ "r|/dev/sdb|", "r|/dev/sdc|", "r|/dev/sdd|", "r|/dev/sde|", "r|/dev/sdf|", "r|/dev/sdg|", "r|/dev/sda|", "a|drbd.*|", "a|/dev/hda|", "a|/dev/hdb2|", "r|.*|", "a|/dev/md0|", "a|/dev/md1|" ]

after this nothing changes, so you need to rebuild your initrd image

cp /boot/initrd-`uname -r`.img /boot/initrd-`uname -r`.img.bak
mkinitrd -f /boot/initrd-`uname -r`.img `uname -r`
reboot

after this you need to rescan vg's

vgscan -vvvvvvv

you should see that the md0 and md1 have been added to the device cache

#device/dev-cache.c:331         /dev/md0: Added to device cache
#device/dev-cache.c:331         /dev/md1: Added to device cache

check this to make sure it is proper (or manually add it for testing this solution):

cat /etc/lvm/cache/.cache | grep md