Tag Archives: lvm

Extending VM LVM disk

I have a CentOS VMs running in VMware, one of the VMs I was running was out of disk space. The disk was originally 85GB, I tried to increase it to 345GB. In an effort to increase the disk size, I tried:

  1. Shutdown the VM
  2. Increase the size of the disk
  3. Power on the VM
  4. Use parted to resize the partition

Unfortunately, step 4 did not work, parted complained that it could not detect the filesystem:

# parted
GNU Parted 2.1
Using /dev/sda
Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted) print
Model: VMware Virtual disk (scsi)
Disk /dev/sda: 344GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos

Number Start End Size Type File system Flags
1 1049kB 538MB 537MB primary ext4 boot
2 538MB 85.9GB 85.4GB primary lvm

(parted) resize
WARNING: you are attempting to use parted to operate on (resize) a file system.
parted's file system manipulation code is not as robust as what you'll find in
dedicated, file-system-specific packages like e2fsprogs.  We recommend
you use parted only to manipulate partition tables, whenever possible.
Support for performing most operations on most types of file systems
will be removed in an upcoming release.
Partition number? 2
Start?  [538MB]?
End?  [85.9GB]? 344GB
Error: Could not detect file system.

It looks like parted does not like LVM. The next thing that I did is to add a new partition, then use ‘pvcreate’ to create a new physical extent, and then add that to the volume group, as seen below:

# parted
GNU Parted 2.1
Using /dev/sda
Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted) print
Model: VMware Virtual disk (scsi)
Disk /dev/sda: 344GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos

Number  Start   End     Size    Type     File system  Flags
 1      1049kB  538MB   537MB   primary  ext4         boot
 2      538MB   85.9GB  85.4GB  primary               lvm

(parted) mkpart
Partition type?  primary/extended? primary
File system type?  [ext2]?
Start? 85.9
End? 344GB
Warning: You requested a partition from 85.9MB to 344GB.
The closest location we can manage is 85.9GB to 344GB.
Is this still acceptable to you?
Yes/No? yes
Warning: WARNING: the kernel failed to re-read the partition table on /dev/sda (Device or resource busy).  As a result, it may not reflect all of your changes until after reboot.
(parted) print
Model: VMware Virtual disk (scsi)
Disk /dev/sda: 344GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos

Number  Start   End     Size    Type     File system  Flags
 1      1049kB  538MB   537MB   primary  ext4         boot
 2      538MB   85.9GB  85.4GB  primary               lvm
 3      85.9GB  344GB   258GB   primary

(parted) quit

#ls -l /dev/sda
sda   sda1  sda2  sda3

# pvcreate /dev/sda3
  dev_is_mpath: failed to get device for 8:3
  Physical volume "/dev/sda3" successfully created
  
# pvs
  PV         VG   Fmt  Attr PSize   PFree
  /dev/sda2  vg0  lvm2 a--   79.50g      0
  /dev/sda3       lvm2 a--  240.00g 240.00g
  
# vgextend  vg0 /dev/sda3
  Volume group "vg0" successfully extended

# vgs
  VG   #PV #LV #SN Attr   VSize   VFree
  vg0    2   4   0 wz--n- 319.49g 240.00g