Add a disk to linux LVM command line

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If your starting from scratch, ‘imaging’ or installing linux , insure you’ve partitioned with setup LVM on the first disk for this guide. As this is just the basic setup.

Once you’ve reached the command line, you can run lsblk to list all block devices, noticing what is a partition and what is a device, where sda would be a device, and sda1 would be a partition:

lsblk

Output:

NAME                 MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
sda                    8:0    0 465.8G  0 disk 
├─sda1                 8:1    0   243M  0 part /boot
├─sda2                 8:2    0     1K  0 part 
└─sda5                 8:5    0 465.5G  0 part 
  ├─bak10--vg-root   254:0    0 465.5G  0 lvm  /
  └─bak10--vg-swap_1 254:1    0     4G  0 lvm  [SWAP]
sdb                    8:16   0 465.8G  0 disk

Once you know the device you want to expand the LVM (Logical Volume Management) in this case ‘sdb’

Take care to notice, there are many disk identifiers aka ‘sda’ depending on the specific distro you are using

First you’ll want to install the required tools:

sudo apt-get install system-config-lvm

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Then run:

sudo vgdisplay

In this case the LVM has already been expanded, either way, take note of the volume group, which you would have been prompted to define during the OS install.

We can see here as the volume group as ‘VG Name’ bak10-vg

Output:

--- Volume group ---
  VG Name               bak10-vg
  System ID             
  Format                lvm2
  Metadata Areas        2
  Metadata Sequence No  5
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                2
  Open LV               2
  Max PV                0
  Cur PV                2
  Act PV                2
  VG Size               931.28 GiB
  PE Size               4.00 MiB
  Total PE              238407
  Alloc PE / Size       238407 / 931.28 GiB
  Free  PE / Size       0 / 0   
  VG UUID               I3z4RM-RAsq-HfPD-FiUo-KxOZ-Jpsg-zROJPt

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We also need the logical volume root path, this can be found by running:

sudo lvdisplay

We can see the volume group root path is ‘LV Path /dev/bak10-vg/root’ Output:

--- Logical volume ---
LV Path                /dev/bak10-vg/root
LV Name                root
VG Name                bak10-vg
LV UUID                ykeSJi-Q1mw-dWui-5D7p-Lr1y-wk18-swWVN8
LV Write Access        read/write
LV Creation host, time bak10, 2016-12-24 10:43:48 -0500
LV Status              available
# open                 1
LV Size                927.28 GiB
Current LE             237383
Segments               2
Allocation             inherit
Read ahead sectors     auto
- currently set to     256
Block device           254:0
 
--- Logical volume ---
LV Path                /dev/bak10-vg/swap_1
LV Name                swap_1
VG Name                bak10-vg
LV UUID                URTRk2-lcke-7oq6-TAtK-EGg8-qyTf-pAmr9Z
LV Write Access        read/write
LV Creation host, time bak10, 2016-12-24 10:43:48 -0500
LV Status              available
# open                 2
LV Size                4.00 GiB
Current LE             1024
Segments               1
Allocation             inherit
Read ahead sectors     auto
- currently set to     256
Block device           254:1

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Now we convert the disk ‘sdb’ into a physical volume by running:

sudo pvcreate /dev/sdb

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Then we add the physical volume to the volume group by extending the existing volume group to the second disk:

sudo vgextend bak10-vg /dev/sdb

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Then we allocate the physical volume to the logical volume. You can allocate a specific partition or percentage of the new disk, however this is basic by adding the complete disk:

sudo lvextend -l +100%FREE /dev/bak10-vg/root

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Now we must resize the volume group to the new physical drive:

sudo resize2fs /dev/bak10-vg/root

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The LVM has been expanded to the second disk ‘/dev/sdb’, where the first disk contains a default and basic partitioning scheme :

lsblk

NAME                 MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
sda                    8:0    0 465.8G  0 disk 
├─sda1                 8:1    0   243M  0 part /boot
├─sda2                 8:2    0     1K  0 part 
└─sda5                 8:5    0 465.5G  0 part 
  ├─bak10--vg-root   254:0    0 927.3G  0 lvm  /
  └─bak10--vg-swap_1 254:1    0     4G  0 lvm  [SWAP]
sdb                    8:16   0 465.8G  0 disk 
└─bak10--vg-root     254:0    0 927.3G  0 lvm  /

None the less, we can see the two available physical disks ‘sda and sdb’ are now part of one file system.

Where sda contains necessary basic partitions, and the second disk is now part of the volume group as usable space.

Fin! Enjoy your new space!