Attempting to increase the size of a Linux LVM Disk

RamblingBiped

If you're wanting to add this to an already existing logical volume you don't need to do anything with the file system at first. You need to add the new physical volume to the volume group that your existing logical volume is on. Once that physical volume has been added to the volume group you can extend the logical volume and increase it's size. At that point you can grow the file system to occupy the newly allocated space.

Here's an article that should help walk you through the process if you're not familiar: http://www.tecmint.com/extend-and-reduce-lvms-in-linux/

wirestyle22

@RamblingBiped So I can unmount it and delete the virtual disk then recreate to start over, correct?

RamblingBiped

@wirestyle22 I think that should work. As long as you can see the disk you should be able to use LVM's pvcreate to create a physical volume and then add that volume to the volume group that is associated with your logical volume.

pvs and pvdisplay will show pertinent information in regards to your LVM physical volumes.

vgs and vgdisplay will show volume group information.

lvs and lvdisplay will show logical volume information.

wirestyle22

@RamblingBiped So I can see that both Logical Volumes and Physical Volumes are added.

The question now is how to add the VFree space to dev/mapper/centos-root

RamblingBiped

@wirestyle22 Did you do an lvextend on the logical volume that you are wanting to add the extra storage space to?

RamblingBiped

@wirestyle22 said in Attempting to increase the size of a Linux LVM Disk:

The question now is how to add the VFree space to dev/mapper/centos-root

So if you do a vgs command it should show your volume group with your newly increased capacity. When you do a lvs it should show your logical volumes (probably root and swap). You'll want to do a lvextend on your root logical volume to add the newly allocated space on the volume group to that logical volume.

The article I linked you previously should give a good example of that command. Google-fu will result in some official redhat documentation that will do a good job of walking you through it too.

Once you've extended your logical volume you'll just need to expand the filesystem to occupy the space. After that you should be all set.

RamblingBiped

Growing Logical Volumes: https://www.centos.org/docs/5/html/Cluster_Logical_Volume_Manager/lv_extend.html

https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/6/html/Logical_Volume_Manager_Administration/lv_extend.html

travisdh1

Let's see if I can remember this without looking anything up this time...

pvcreate /dev/new_drive
vgextend vg_name /dev/new_drive
lvextend lv_name -l 100%FREE

Dang, I forget the ones to extend the file system

wirestyle22

@travisdh1 My problem is LVS and VGS displays the right amout of space.PVS displays two PV's in the same VG, both at 1.95TB but nothing is listed as VFree.

vgs

lvs

pvs

df -h

scottalanmiller

Have you expanded the filesystem yet?

wirestyle22

@scottalanmiller

resize2fs /dev/mapper/centos-root

[root@localhost ~]# resize2fs /dev/mapper/centos-root 3.91T
resize2fs 1.42.9 (28-Dec-2013)
resize2fs: Bad magic number in super-block while trying to open /dev/mapper/centos-root
Couldn't find valid filesystem superblock.

scottalanmiller

That's not good. Try it with the -p flag.

scottalanmiller

What filesystem do you have? Could it be XFS?

scottalanmiller

If XFS the command syntax is...

xfs_growfs /mount/point -D size

scottalanmiller

It's XenServer, we are expecting EXT4 here, right?

wirestyle22

@scottalanmiller Correct

wirestyle22

Is this improper syntax?

stacksofplates

@wirestyle22 said in Attempting to increase the size of a Linux LVM Disk:

Is this improper syntax?

Try +3.91.

Also, why not have the data on its own volume? It's more flexible that way.

stacksofplates

If the +doesn't work you will have to add it to the existing size. So if its 5TB it would be 8.91

scottalanmiller

Just appears that the size is too small.