Expanding Storage

Existing System
Number of Hard drives: 3
Partitions per drive: 2
Size of each partition: 250023 bytes

  1. Shutdown box

    sudo halt -p

  2. Install new SATA drive.
  3. Turn on the power.
  4. Partition the drive (of the size above) using type: FD
  5. Maximize the RAID’s minimum build speed:

    echo '150000' > /proc/sys/dev/raid/speed_limit_min

  6. Unmount the filesystem underwhich the Volume Group exists

    sudo umount /share

  7. Add the partition(s) to each RAID5 array

    sudo mdadm --add /dev/md0 /dev/sde1
    sudo mdadm --add /dev/md1 /dev/sde2

  8. Grow the array

    sudo mdadm --grow /dev/md0 --raid-disks=4
    sudo mdadm --grow /dev/md1 --raid-disks=4

  9. WAIT TILL THE REBUILDING IS DONE!

    Note: One array will be rebuilding while the other is queued until the first one finishes. If for any reason you had to stop the array from rebuilding, you can start it again using:

    mdadm -A --force /dev/md0 /dev/sdb1 /dev/sdc1 /dev/sdd1 /dev/sde1
    mdadm -A --force /dev/md1 /dev/sdb2 /dev/sdc2 /dev/sdd2 /dev/sde2

    The above is because the config file of mdadm was not updated (yet) and still counts the new partitions as spares. After issuing the commands above, wait untill the array is finished rebuilding.

  10. Update the mdadm config file:
    sudo su
    mdadm --misc --detail --brief /dev/md0 > /etc/mdadm/mdadm.conf
    mdadm --misc --detail --brief /dev/md1 >> /etc/mdadm/mdadm.conf

    11. or use “–scan” to include all arrays

  11. Grow the Physical Volume (PV)
    sudo pvresize /dev/md0

    Physical volume "/dev/md0" changed
    1 physical volume(s) resized / 0 physical volume(s) not resized

    sudo pvdisplay /dev/md0

    --- Physical volume ---
    PV Name /dev/md0
    VG Name arrays
    PV Size 698.56 GB / not usable 570.81 MB
    Allocatable yes
    PE Size (KByte) 1048576
    Total PE 698
    Free PE 233
    Allocated PE 465
    PV UUID XpucQy-CP8u-gr5B-trw1-alB3-j25u-RBWs1y

    Notice the Free PE. The same can be done to md1 or more arrays

  12. Extend the Logical Volume (LV)

    sudo lvextend -l +100%FREE /dev/arrays/zastoraje

    Extending logical volume zastoraje to 1.36 TB
    Logical volume zastoraje successfully resized

  13. Check the Volume Group

    sudo vgdisplay

    --- Volume group ---
    VG Name arrays
    System ID
    Format lvm2
    Metadata Areas 2
    Metadata Sequence No 8
    VG Access read/write
    VG Status resizable
    MAX LV 0
    Cur LV 1
    Open LV 0
    Max PV 0
    Cur PV 2
    Act PV 2
    VG Size 1.36 TB
    PE Size 1.00 GB
    Total PE 1396
    Alloc PE / Size 1396 / 1.36 TB
    Free PE / Size 0 / 0
    VG UUID 5czGLh-DvVO-nDBa-QTCy-x5zR-QUti-Lz0103

  14. Remount directory

    sudo mount /share

  15. Grow the filesystem

    sudo xfs_growfs /share

    meta-data=/dev/mapper/arrays-zastoraje isize=256 agcount=32, agsize=7618560 blks
    = sectsz=512 attr=0
    data = bsize=4096 blocks=243793920, imaxpct=25
    = sunit=0 swidth=0 blks, unwritten=1
    naming =version 2 bsize=4096
    log =internal bsize=4096 blocks=16384, version=1
    = sectsz=512 sunit=0 blks, lazy-count=0
    realtime =none extsz=4096 blocks=0, rtextents=0
    data blocks changed from 243793920 to 365953024

  16. Check the free space

    17. df -h

    Filesystem Size Used Avail Use% Mounted on
    /dev/sda1 71G 948M 67G 2% /
    varrun 502M 188K 502M 1% /var/run
    varlock 502M 0 502M 0% /var/lock
    udev 502M 112K 502M 1% /dev
    devshm 502M 0 502M 0% /dev/shm
    /dev/mapper/arrays-zastoraje
    1.4T 730G 667G 53% /share

  17. Done!

    Updated System
    Number of Hard drives: 4
    Partitions per drive: 2
    Size of each partition: 250023 bytes