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

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

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

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

sudo pvcreate /dev/sdb

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

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

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

sudo resize2fs /dev/bak10-vg/root

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!

The formatting here is simple enough to understand (I would hope). ^ means ctrl+, so ^x is ctrl+x. M- means meta (generally left-alt or escape)+, so M-x is left-alt+x It should be noted that this is no where near a full feature-set of either group. This - being a cheat-sheet - is just to point out the most very basic features to get you on the road. Trust the developers and manpage writers more than me. This document is originally from 2009 when tmux was still new - since then both of these programs have had many updates and features added (not all of which have been dutifully noted here).
Action	tmux	screen
start a new session	tmux OR tmux new OR tmux new-session	screen
re-attach a detached session	tmux attach OR tmux attach-session	screen-r
re-attach an attached session (detaching it from elsewhere)	tmux attach -d OR tmux attach-session -d	screen -dr
re-attach an attached session (keeping it attached elsewhere)	tmux attach OR tmux attach-session	screen -x
detach from currently attached session	^b d OR ^b :detach	^a ^d OR ^a :detach
rename-window to newname	^b , <newname> OR ^b :rename-window <newn>	^a A <newname>
list windows	^b w	^a w
list windows in chooseable menu		^a "
go to window #	^b #	^a #
go to last-active window	^b l	^a ^a
go to next window	^b n	^a n
go to previous window	^b p	^a p
see keybindings	^b ?	^a ?
list sessions	^b s OR tmux ls OR tmux list-sessions	screen -ls
toggle visual bell		^a ^g
create another window	^b c	^a c
exit current shell/window	^d	^d
split window/pane horizontally	^b "	^a S
split window/pane vertically	^b %	^a \|
switch to other pane	^b o	^a <tab>
kill the current pane	^b x OR (logout/^D)
collapse the current pane/split (but leave processes running)		^a X
cycle location of panes	^b ^o
swap current pane with previous	^b {
swap current pane with next	^b }
show time	^b t
show numeric values of panes	^b q
toggle zoom-state of current pane (maximize/return current pane)	^b z
break the current pane out of its window (to form new window)	^b !
re-arrange current panels within same window (different layouts)	^b [space]
Kill the current window (and all panes within)	^b killw [target-window]

Add a disk to linux LVM command line

screen and tmux