[LVM] It is not possible to increase VG

[jonnathanclay]

Hello community
I am trying to increase the size of a VG and I ran into several problems, these are the steps that I executed:

Add additional disk space. When executing fdisk -l to verify the space it showed me this message:



GPT PMBR size mismatch (41943039 != 62914559) will be corrected by write.The backup GPT table is not on the end of the device. This problem will be corrected by write.
Disk /dev/sda: 30 GiB, 32212254720 bytes, 62914560 sectors
Disk model: QEMU HARDDISK
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: gpt
Disk identifier: FA3DBA3B-C8B5-45A6-AE60-8FA3EF5C9794


Device Start End Sectors Size Type
/dev/sda1 2048 4095 2048 1M BIOS boot
/dev/sda2 4096 2101247 2097152 1G Linux filesystem
/dev/sda3 2101248 25163775 23062528 11G Linux filesystem

I googled and found that I had to enter the parted application to correct it, then I did the following:


root@container:~# partedGNU Parted 3.3
Using /dev/sda
Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted) help
align-check TYPE N check partition N for TYPE(min|opt) alignment
help [COMMAND] print general help, or help on COMMAND
mklabel,mktable LABEL-TYPE create a new disklabel (partition table)
mkpart PART-TYPE [FS-TYPE] START END make a partition
name NUMBER NAME name partition NUMBER as NAME
print [devices|free|list,all|NUMBER] display the partition table, available devices, free space, all found partitions, or a particular partition
quit exit program
rescue START END rescue a lost partition near START and END
resizepart NUMBER END resize partition NUMBER
rm NUMBER delete partition NUMBER
select DEVICE choose the device to edit
disk_set FLAG STATE change the FLAG on selected device
disk_toggle [FLAG] toggle the state of FLAG on selected device
set NUMBER FLAG STATE change the FLAG on partition NUMBER
toggle [NUMBER [FLAG]] toggle the state of FLAG on partition NUMBER
unit UNIT set the default unit to UNIT
version display the version number and copyright information of GNU Parted
(parted) print
Warning: Not all of the space available to /dev/sda appears to be used, you can fix the GPT to use all of the space (an extra 20971520 blocks) or continue with the current setting?


Fix/Ignore? Fix
Model: QEMU QEMU HARDDISK (scsi)
Disk /dev/sda: 32.2GB
Sector size (logical/physical): 512B/512B
Partition Table: gpt
Disk Flags:


Number Start End Size File system Name Flags
1 1049kB 2097kB 1049kB bios_grub
2 2097kB 1076MB 1074MB ext4
3 1076MB 12.9GB 11.8GB

It no longer shows me the GPT PMBR message, so I check the volume information


root@container:~# df -h |grep ubuntu--vg-ubuntu
/dev/mapper/ubuntu--vg-ubuntu--lv 11G 8.8G 1.5G 86% /

root@container:~# lvs
LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert
ubuntu-lv ubuntu-vg -wi-ao---- <11.00g
lv-0 vg0 -wi-ao---- <500.00g

root@container:~# vgs
VG #PV #LV #SN Attr VSize VFree
ubuntu-vg 1 1 0 wz--n- <11.00g 0
vg0 1 1 0 wz--n- <500.00g 0

I try to extend the space of the ubuntu-vg


root@container:~# vgextend ubuntu-vg /dev/sda
Device /dev/sda excluded by a filter.

I check inside the /etc/lvm/lvm.conf file if there is any uncommented filter and I can't find any

Of course this doesn't work either since I don't have free space on the VG


root@container:~# lvextend /dev/ubuntu-vg/ubuntu-lv -l +100%FREE -r Size of logical volume ubuntu-vg/ubuntu-lv unchanged from <11.00 GiB (2815 extents).
Logical volume ubuntu-vg/ubuntu-lv successfully resized.
resize2fs 1.45.5 (07-Jan-2020)
The filesystem is already 2882560 (4k) blocks long. Nothing to do!

I tried this that I read in a corner of the internet that could work


root@container:~# wipefs -a /dev/sda
wipefs: error: /dev/sda: probing initialization failed: Device or resource busy

I don't know what to do anymore, could someone please help me

All of this is happening under Ubuntu 20.04.2

[volkswagner]

I'm no expert but at a quick glance, I expected to see a pvextend command.
You grew the partition but didn't grow the physical volume before extending
the volume group.

I look at LVM as hierarchal:
PV
--VG
----LV

[darkod]

After you tried the fix in parted, is that output how currently the disk is? I mean it says sda3 is 12GB but you made the disk to be 30GB I understand. So you would want now to resize the partition, yes?

Before you even get to LVM tools, you need to take care of the disk first. You have two options:

1). Resize current sda3 partition.
2). Create new sda4 partition and use it as PV for LVM too.

Depending what you choose to do, the commands for LVM after that will be slightly different.

1). You need to use pvresize to make it use the new size of sda3.
2). You use pvcreate to start the process to use sda4 in the LVM.

If you need more help after completing these steps, ask here. Be careful of not running any command that you see fit unless you really know what it is for. That is if you care for the data on the disk. Otherwise simply format it and start from zero and problem solved.

For example that wipefs is making me nervous. Maybe because I've never seen it before. :) If you have data that you want to keep, I would be very careful with commands having 'wipe' in their name.

[jonnathanclay]

Thanks for the answers

Do the following:


Free space available in sda and sda3



root@container:~# fdisk /dev/sda

Welcome to fdisk (util-linux 2.34).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.




Command (m for help): F
Unpartitioned space /dev/sda: 18 GiB, 19328384512 bytes, 37750751 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes


Start End Sectors Size
25163776 62914526 37750751 18G



root@container:~# fdisk /dev/sda3

Welcome to fdisk (util-linux 2.34).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.


The old LVM2_member signature will be removed by a write command.


Device does not contain a recognized partition table.
Created a new DOS disklabel with disk identifier 0x9ad59447.


Command (m for help): F
Unpartitioned space /dev/sda3: 10.102 GiB, 11806965760 bytes, 23060480 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes


Start End Sectors Size
2048 23062527 23060480 11G


root@container:~# pvdisplay
--- Physical volume ---
PV Name /dev/sdb
VG Name vg0
PV Size 500.00 GiB / not usable 4.00 MiB
Allocatable yes (but full)
PE Size 4.00 MiB
Total PE 127999
Free PE 0
Allocated PE 127999
PV UUID Lkw4CF-yS4I-Vcld-UMuR-eiwz-bwiU-xw3Wgt

--- Physical volume ---
PV Name /dev/sda3
VG Name ubuntu-vg
PV Size <11.00 GiB / not usable 1.00 MiB
Allocatable yes (but full)
PE Size 4.00 MiB
Total PE 2815
Free PE 0
Allocated PE 2815
PV UUID oFuEAI-onjW-3Gki-J77s-fDSt-PYRJ-7Gc11O

It does not make any changes, I understand that sda3 still does not have free space available and I do not know how to allocate it


root@container:~# pvresize /dev/sda3 Physical volume "/dev/sda3" changed
1 physical volume(s) resized or updated / 0 physical volume(s) not resized
root@container:~#

Maybe something needs to be done on the partition table?

[jonnathanclay]

I made it!

root@container:~# df -h |grep ubuntu
/dev/mapper/ubuntu--vg-ubuntu--lv 29G 8.8G 19G 33% /


I found a detailed tutorial of the steps to follow, I hope it can help more people

English (https://theducks.org/2009/11/expanding-lvm-partitions-in-vmware-on-the-fly/) (ext4 FS)
Spanish (https://www.ionos.es/ayuda/servidores-cloud/administracion-del-servidor/adaptar-el-volumen-logico-despues-de-ampliar-la-ssd/adaptar-el-volumen-logico-despues-de-haber-ampliado-el-disco-ssd-en-centos-8-cloud-server/) (xfs FS)

The last command may vary if the FS is ext4 or xfs

[TheFu]

All the *display commands are old-school. Most of the time, we only need summaries of the relevant LVM information.

sudo pvs
sudo vgs
sudo lvs
provides the complete view of LVM objects and LVM storage.

For a nice overview of all storage, lsblk -e 7 -o name,size,type,fstype,mountpoint is a very handy alias, as is df -hT -x squashfs -x tmpfs -x devtmpfs