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I created RAID 5 form 3 hard drives. Formatted as ext4 this raid array. Created VG0 group and lv_home logical volume in LVM. Then I tried to mount default /home directory on lv_home, while trying to mount logical volume lv_home to folder containing user profiles /home, getting error:

mount: wrong fs type, bad option, bad superblock on /dev/mapper/VG0-lv_home

next is seems to be symbolic link:

# file -s /dev/VG0/lv_home
/dev/VG0/lv_home: symbolic link to `../mapper/VG0-lv_home'


# file -s /dev/mapper/VG0-lv_home
/dev/mapper/VG0-lv_home: data


lvm> pvs
  PV         VG   Fmt  Attr PSize PFree 
  /dev/md0   VG0  lvm2 a-   2.02g 68.00m
lvm> lvdisplay
  --- Logical volume ---
  LV Name                /dev/VG0/lv_home
  VG Name                VG0
  LV UUID                WzJus7-2yV8-yhog-Ju1b-TpWH-IIAI-LIutwe
  LV Write Access        read/write
  LV Status              available
  # open                 0
  LV Size                1.17 GiB
  Current LE             300
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     256
  Block device           251:0


When dmesg | grep md0 I've got md0: unknown partition table. I did raid, pv, vg, lv, formatted mkfs.ext4 /dev/VG0/lv_home, updated /etc/fstab - but still getting error. I was able to mount only with mount -f /dev/md0. I can write files to mounted /dev/md0 at /tmp_home. What seems to be a problem? UPDATE 2

I can mount only LV, but not raid5 (/dev/md0/):

# mount -t ext4 /dev/VG0/lv_home /mnt/tmp_home
# mount
/dev/sda1 on / type ext4 (rw,errors=remount-ro)
proc on /proc type proc (rw,noexec,nosuid,nodev)
none on /sys type sysfs (rw,noexec,nosuid,nodev)
none on /sys/fs/fuse/connections type fusectl (rw)
none on /sys/kernel/debug type debugfs (rw)
none on /sys/kernel/security type securityfs (rw)
none on /dev type devtmpfs (rw,mode=0755)
none on /dev/pts type devpts (rw,noexec,nosuid,gid=5,mode=0620)
none on /dev/shm type tmpfs (rw,nosuid,nodev)
none on /var/run type tmpfs (rw,nosuid,mode=0755)
none on /var/lock type tmpfs (rw,noexec,nosuid,nodev)
none on /lib/init/rw type tmpfs (rw,nosuid,mode=0755)
/dev/sda6 on /var type xfs (rw)
/dev/md1 on /export type xfs (rw)
none on /proc/fs/vmblock/mountPoint type vmblock (rw)
/dev/mapper/VG0-lv_home on /mnt/tmp_home type ext4 (rw)

Is it correct?

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up vote 1 down vote accepted

You say:

I created RAID 5 form 3 hard drives. Formatted as ext4 this raid array.

What you actually need to do is:

  • Create a RAID
  • Create a PV out of the RAID device (/dev/md0 in your case)
  • Create a VG out of that PV (VG0 in your case)
  • Make one or more LVs in that VG, e.g. one for /, another for /home, etc.
  • Format each of these LVs separately (e.g. as ext4)
  • Mount them wherever you want after they are formatted

Formatting a RAID device that you are going to use for LVM is not needed and doesn't serve a purpose. Take a look at this great tutorial for a more general overview of LVM (though not RAID from what I see, but I see you already got that part done):

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