mirror of
https://github.com/PhyllomeOS/wiki.git
synced 2024-12-22 05:35:22 +00:00
135 lines
3.7 KiB
Markdown
135 lines
3.7 KiB
Markdown
---
|
||
title: Resize an existing virtual disk
|
||
description:
|
||
published: true
|
||
date: 2024-07-13T13:33:59.560Z
|
||
tags:
|
||
editor: markdown
|
||
dateCreated: 2021-11-13T11:41:29.087Z
|
||
---
|
||
|
||
# Resize a disk
|
||
|
||
## Background
|
||
|
||
A virtual machine's disk may have to be resized, typically due to lack of space. This page explains how to do so.
|
||
|
||
## Usage for Linux guests
|
||
|
||
> In-place expansion is not supported. A new disk of the desired size has to be created.
|
||
{.is-info}
|
||
|
||
* Navigate to the location that contains the existing image
|
||
|
||
```
|
||
cd /var/lib/libvirt/images
|
||
```
|
||
|
||
* Create a new blank disk image of the desired size
|
||
|
||
Use the following command to create a disk of 20 GB called `guest_20G.img`.
|
||
|
||
```
|
||
qemu-img create -f raw guest_20G.img 20G
|
||
```
|
||
|
||
* Identify the filesystem layout of the existing disk `guest.img`
|
||
|
||
```
|
||
# virt-filesystems -a -l -h guest.img
|
||
Name Type VFS Label Size Parent
|
||
/dev/vda1 filesystem vfat EFI 133935104 -
|
||
/dev/vda2 filesystem ext4 boot 366869504 -
|
||
/dev/vda3 filesystem ext4 root 9933475840 -
|
||
```
|
||
|
||
One can tell that the root partition is located under `/dev/vda3`. This is the one that will need to be expanded.
|
||
|
||
* Copy the formet old data to the new disk and expand the root partition of the said disk
|
||
|
||
> This command is cabable of expanding different kinds of filesystems, including `ext4` and `btrfs`
|
||
{.is-info}
|
||
|
||
```
|
||
# virt-resize --expand /dev/vda3 guest.img guest_20G.img
|
||
```
|
||
|
||
* Review the changes
|
||
|
||
```
|
||
[ 0.0] Examining guest_20G.img
|
||
**********
|
||
|
||
Summary of changes:
|
||
|
||
/dev/vda1: This partition will be left alone.
|
||
|
||
/dev/vda2: This partition will be left alone.
|
||
|
||
/dev/vda3: This partition will be resized from 10G to 20G. The
|
||
filesystem ext4 on /dev/vda3 will be expanded using the ‘resize2fs’
|
||
method.
|
||
|
||
**********
|
||
[ 2.1] Setting up initial partition table on guest_20G.img
|
||
[ 12.9] Copying /dev/vda1
|
||
[ 13.1] Copying /dev/vda2
|
||
[ 13.4] Copying /dev/vda3
|
||
100% ⟦▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒⟧ 00:00
|
||
[ 38.3] Expanding /dev/vda3 using the ‘resize2fs’ method
|
||
|
||
Resize operation completed with no errors. Before deleting the old disk,
|
||
carefully check that the resized disk boots and works correctly.
|
||
```
|
||
|
||
* Switch to the new disk for your virtual machine
|
||
|
||
Now that the new disk has been created, it can be used in the virtual machine.
|
||
|
||
```
|
||
# virsh edit guest
|
||
```
|
||
|
||
Locate the source line for the existing disk `guest.img`:
|
||
|
||
```
|
||
[...]
|
||
<disk type='file' device='disk'>
|
||
<driver name='qemu' type='raw' cache='writeback' discard='unmap'/>
|
||
<source file='/var/lib/libvirt/images/guest.img'/>
|
||
<target dev='vda' bus='virtio'/>
|
||
<address type='pci' domain='0x0000' bus='0x04' slot='0x00' function='0x0'/>
|
||
</disk>
|
||
[...]
|
||
```
|
||
|
||
Edit the said line so that it points to the new disk `guest-20G.img`:
|
||
|
||
```
|
||
[...]
|
||
<disk type='file' device='disk'>
|
||
<driver name='qemu' type='raw' cache='writeback' discard='unmap'/>
|
||
<source file='/var/lib/libvirt/images/guest-20G.img'/>
|
||
<target dev='vda' bus='virtio'/>
|
||
<address type='pci' domain='0x0000' bus='0x04' slot='0x00' function='0x0'/>
|
||
</disk>
|
||
[...]
|
||
```
|
||
|
||
Start the virtual machine and ensure that it is working properly. If it does, the former disk could be removed.
|
||
|
||
## Resources
|
||
|
||
As per the software description : "*qemu-img allows you to create, convert and modify images offline. It can handle all image formats supported by QEMU.*"
|
||
|
||
* Installation
|
||
|
||
On Fedora-related distributions, `virt-resize` is provided by the `guestfs-tools` package :
|
||
|
||
```
|
||
# dnf install guestfs-tools
|
||
```
|
||
|
||
---
|
||
|
||
*[**Go to parent page**](https://wiki.phyllo.me/)* |