Increase partition size on which Ubuntu is installed?
As a matter of fact, you CAN enlarge the root filesystem while Ubuntu is running (I learned this recently myself here) - this sounds incredible but it's true :)
Here's the list of steps for a simple scenario where you have two partitions, /dev/sda1
is an ext4 partition the OS is booted from and /dev/sdb2
is swap. For this exercise we want to remove the swap partition an extend /dev/sda1
to the whole disk.
As always, make sure you have a backup of your data - since we're going to modify the partition table there's a chance to lose all your data if you make a typo, for example.
Run
sudo fdisk /dev/sda
- use
p
to list the partitions. Make note of the start cylinder of/dev/sda1
- use
d
to delete first the swap partition (2
) and then the/dev/sda1
partition. This is very scary but is actually harmless as the data is not written to the disk until you write the changes to the disk. - use
n
to create a new primary partition. Make sure its start cylinder is exactly the same as the old/dev/sda1
used to have. For the end cylinder agree with the default choice, which is to make the partition to span the whole disk. - use
a
to toggle the bootable flag on the new/dev/sda1
- review your changes, make a deep breath and use
w
to write the new partition table to disk. You'll get a message telling that the kernel couldn't re-read the partition table because the device is busy, but that's ok.
- use
Reboot with
sudo reboot
. When the system boots, you'll have a smaller filesystem living inside a larger partition.The next magic command is
resize2fs
. Runsudo resize2fs /dev/sda1
- this form will default to making the filesystem to take all available space on the partition.
That's it, we've just resized a partition on which Ubuntu is installed, without booting from an external drive.
Two Methods
1. Tested in Ubuntu Server 16.04 to 18.10
After extending the volume in VMware ESXi (shutdown vm, backup/export vm, remove all snapshots, then increased number in disk size, take snapshot of vm again before following the next steps so you can revert mistake/error).
The following example is extending volume on root partition on a system that is already using LVM.
ssh
into the system, switch to root and runcfdisk
# cfdiskAfter exiting cfdisk
# fdisk -l /dev/sda Disk /dev/sda: 20 GiB, 21474836480 bytes, 41943040 sectors 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: dos Disk identifier: 0xc8b647ff Device Boot Start End Sectors Size Id Type /dev/sda1 * 2048 999423 997376 487M 83 Linux /dev/sda2 1001470 16775167 15773698 7.5G 5 Extended /dev/sda3 16775168 41943039 25167872 12G 8e Linux LVM (***** See new partition /dev/sda3*****) /dev/sda5 1001472 16775167 15773696 7.5G 8e Linux LVM
Reboot system before next step (or else you might get
Device /dev/sda3 not found (or ignored by filtering)
)# shutdown now -r
Initialize the new volume
# pvcreate /dev/sda3 Physical volume "/dev/sda3" successfully created
Get the name of volume to extend
# vgdisplay --- Volume group --- VG Name linuxetc1-vg (***** this is vg i'm extending*****) System ID Format lvm2 Metadata Areas 1 Metadata Sequence No 3 VG Access read/write VG Status resizable MAX LV 0 Cur LV 2 Open LV 2 Max PV 0 Cur PV 1 Act PV 1 VG Size 7.52 GiB PE Size 4.00 MiB Total PE 1925 Alloc PE / Size 1925 / 7.52 GiB Free PE / Size 0 / 0 ...
Extend volume group
# vgextend linuxetc1-vg /dev/sda3 Volume group "linuxetc1-vg" successfully extended
Extend root
# lvextend -l+100%FREE /dev/linuxetc1-vg/root Size of logical volume linuxetc1-vg/root changed from 6.52 GiB (1669 extents) to 18.52 GiB (4741 extents). Logical volume root successfully resized. Or if you only wanted to give 5 more GB to root # lvextend -L +5g /dev/linuxetc1-vg/root
Get filesystem name for next step
# df -h Filesystem Size Used Avail Use% Mounted on udev 477M 0 477M 0% /dev tmpfs 100M 4.6M 95M 5% /run /dev/mapper/linuxetc1--vg-root 6.3G 2.5G 3.5G 42% / (***** this line*****) tmpfs 497M 0 497M 0% /dev/shm tmpfs 5.0M 0 5.0M 0% /run/lock tmpfs 497M 0 497M 0% /sys/fs/cgroup /dev/sda1 472M 105M 343M 24% /boot tmpfs 100M 0 100M 0% /run/user/1000
Extend filesystem
# resize2fs /dev/mapper/linuxetc1--vg-root resize2fs 1.42.13 (17-May-2015) Filesystem at /dev/mapper/linuxetc1--vg-root is mounted on /; on-line resizing required old_desc_blocks = 1, new_desc_blocks = 2 The filesystem on /dev/mapper/linuxetc1--vg-root is now 4854784 (4k) blocks long.
See the increased size
# df -h Filesystem Size Used Avail Use% Mounted on udev 477M 0 477M 0% /dev tmpfs 100M 4.6M 95M 5% /run /dev/mapper/linuxetc1--vg-root 19G 2.5G 15G 15% / (***** this line*****) tmpfs 497M 0 497M 0% /dev/shm tmpfs 5.0M 0 5.0M 0% /run/lock tmpfs 497M 0 497M 0% /sys/fs/cgroup /dev/sda1 472M 105M 343M 24% /boot tmpfs 100M 0 100M 0% /run/user/1000
2. Faster Method Tested in Ubuntu Server 18.04.3 LTS
This method is a little faster than the first. This is due to a new option in the cfdisk
menu called "Resize" that saves some steps.
After extending the volume in VMware ESXi (shutdown vm, backup/export vm, remove all snapshots, then increased number in disk size, take snapshot of vm again before following the next steps so you can revert mistake/error).
The following example is extending volume on root partition on a system that is already using LVM.
ssh
into the system, switch to root and runcfdisk
.Choose the partition to extend and select "Resize".
Set the "New size".
After pressing enter, you'll see screen with the following note "Partition [someNumber] resized":
Next you'll need to "Write" (save) your changes:
Quit
cfdisk
. When you exit you may see message "syncing disks".I rebooted my system at this point but it may not be necessary. Now you can pickup from step 19 from the first method (repeated below).
(19) Get filesystem name for next step
# df -h Filesystem Size Used Avail Use% Mounted on udev 477M 0 477M 0% /dev tmpfs 100M 4.6M 95M 5% /run /dev/mapper/linuxetc1--vg-root 6.3G 2.5G 3.5G 42% / (***** this line*****) tmpfs 497M 0 497M 0% /dev/shm tmpfs 5.0M 0 5.0M 0% /run/lock tmpfs 497M 0 497M 0% /sys/fs/cgroup /dev/sda1 472M 105M 343M 24% /boot tmpfs 100M 0 100M 0% /run/user/1000
(20) Extend filesystem
# resize2fs /dev/mapper/linuxetc1--vg-root resize2fs 1.42.13 (17-May-2015) Filesystem at /dev/mapper/linuxetc1--vg-root is mounted on /; on-line resizing required old_desc_blocks = 1, new_desc_blocks = 2 The filesystem on /dev/mapper/linuxetc1--vg-root is now 4854784 (4k) blocks long.
(21) See the increased size
# df -h Filesystem Size Used Avail Use% Mounted on udev 477M 0 477M 0% /dev tmpfs 100M 4.6M 95M 5% /run /dev/mapper/linuxetc1--vg-root 19G 2.5G 15G 15% / (***** this line*****) tmpfs 497M 0 497M 0% /dev/shm tmpfs 5.0M 0 5.0M 0% /run/lock tmpfs 497M 0 497M 0% /sys/fs/cgroup /dev/sda1 472M 105M 343M 24% /boot tmpfs 100M 0 100M 0% /run/user/1000
Articles:
https://wiki.ubuntu.com/Lvm
http://www.geoffstratton.com/expand-hard-disk-ubuntu-lvm
You are almost there.
You can not resize the partition using GParted while Ubuntu is running.
You will need to attach the GParted ISO's as a CD to the VM machine and reboot the machine so that the GParted will be loaded instead of Ubuntu (I think you can boot from the virtual CD by pressing F12 immediately after machine is started).
Once you booted into GParted the option to move/resize will be enabled as Ubuntu is not currently running.