What is Disk Image?
A disk image, a single compressed file, is an exact copy of computer's hard drive, which holds alldata including operating system installation, boot information, applications, and individual files.Why need to create a disk image? Normally, disk imaging is used in several major areas:
Data Protection: Most users create a disk image to prevent data loss from avirus, system crash or disk failure. Just like our human beings, every hard drive is going todie eventually. If so, you can buy a new hard drive and replace the dead one, and then restoredisk image to bring your computer to the state when it works well and all data is intact.
System Migration: Because the performance of SSD is better than HDD, moreand more people are more willing to clone HDD to SSD or migrate OS to another computer withbetter hardware. Thus, disk imaging is an alternative way to directly clone. Also, you can create a system image.
OS Deployment: Large companies often need to buy large numbers of newcomputers with same or different hardware. Installing operating system and programs into each ofthem one by one requires a lot of time and effort and has a significant possibility of humanerror. Therefore, system administrators create a disk image with fully prepared applicationsenvironment of a well-adjust system to quickly deploy it to each computer by using PXE networkboot. This method saves time and effort.
Windows now creates the image file. Create a System Repair Disc. Next, you'll want to create a system repair disc to use if Windows is ever incapable of booting up on its own. To do this at the. It allows more than one image to be reproduced on a hard disk so that users can take back up of more than one computer into the destination disk. The image has to be restored and installed on another computer to start working. Disk imaging software creates an archive of the source disk that can be used to create a back-up copy of the source disk. It is a good thing to create an image of your hard disk. With the image, you can use the image to get back the necessary data when you need it the most. These disc images software is best in their work and protects your data by making a copy of it. The tools can simplify your work and speed up the process in no time.
Choose the Best Disk Imaging Software
When looking for a free disk imaging software, it is important to make an informed decision onwhich product is right for you. The following criteria can help you evaluate the best hard driveimaging software.
Create Disk Image Dd
Set and Forget - The data on disk is modified, updated and added everyday.For data protection, you may don't have enough time to create a full disk image day by day,which will waste time and disk space. Thus, a program which has the ability to automaticallycreate hard drive image and only save changes into disk image (known as incremental &differential backups) is an important criteria.
Universal Restore - The best disk imaging software not only enables you tocreate a disk image, but also allows you to restore a disk image to different environments. Forexample, restore disk image to a hard drive having different size, to a computer havingdissimilar hardware, to an unbootable system, etc.
Compatibility - The best hard disk imaging software should keep abreast ofthe latest technologies, such as Windows 10, GPT/UEFI, dynamic disk and so on.
AOMEI Backupper Standard is a powerful imagetool which not only meets the requirements above, but also is FREE to use. It supports Windows 10,Windows 8.1/8, Windows 7, Vista and XP.
How to Create A Disk Image with Free AOMEI Backupper?
1.Download, install and launch AOMEIBackupper. Move your mouse pointer to 'Backup' and click on it. Then, choose 'Disk Backup' from theright list. After that, you will set up something.
2. First, you are able to edit the default 'Task Name'. Then click 'Add Disk' to choose the disk.
3. Select the disk which you want to create an image.
4. The program also has automatically selected a location where to save disk imagefile. You can click on it to choose another location. To save a disk image to a local disk, anexternal hard drive, a USB flash drive or CD/DVD, please click 'This PC' (or 'Computer') and choosethe destination. (You can also save a disk image to NAS devices or network drive by clicking'Share/NAS).
5. You have almost finished. However, to ensure your disk image is up-to-date, you'dbetter create a scheduled disk image backup by ticking the checkbox before 'Schedule'. Here you can choose frommultiple schedules, such as daily, weekly and monthly. After clicking 'Advanced', you can choose howto schedule the disk image from full backup, incremental backup or differential backup.
Besides, you can configure backup settings by clicking 'Options'. http://nvhmda.xtgem.com/Blog/__xtblog_entry/19154112-keying-makes-adobe-premiere-pro-slow-mac#xt_blog. For example, write a comment andcompress the disk image with a higher level, etc. Encrypting the system image with a password isonly available in Professionaledition.
6. Either the 'Schedule' or 'Options' is optional according to your requirements. Tocreate a disk image, click 'Start Backup'.
How to Do Disk Image Recovery?
AOMEI Backupper provides fast and flexible disk image recovery solutions:
If your system crashes or disk fails, you can use Create Bootable Media to make a Windows PEbootable USB or CD to start up computer and then perform disk image recovery.
If you only want to choose individual files but not entire disk image to restore, you can useExplore Image to mount disk image as virtualpartitions and copy data.
If you want to replace your old computer with a new computer with different hardware, you canuse Universal Restore in Professionalto perform hard drive image recovery.
If you want to deploy a disk image to multiple computers instead of one by one manualrestoration, you can use AOMEI Image Deploy toperform image deployment.
This page documents how to create a hard disk image in QEMU.
The command[edit]
The standard command for creating a basic hard disk image is this.
Create Disk Image Pc
It will create an output similar to this:
The command is broken down like this:
- qemu-img - This is the name of the program. It is necessary for using the following command.
- create - This tells qemu-img that we are creating a disk image. Other arguments include 'dd', 'info', 'map', 'measure', 'snapshot', 'rebase', and 'resize'. This will be described in more detail later on.
- -f - An argument that specifies which file format we are going to be using.
- qcow2 - The file format we are using, in this case qcow2. qcow2 is the recommended since it is dynamically allocated - e.g. it only allocates space when needed, but at a (pretty much) unnoticeable speed loss. There are many other file formats, which will be listed below.
- example.img - This specifies the name of the image we are going to be using. It can be whatever, and have whatever extension (or none at all), it doesn't matter.
- 100M - This specifies the size of the virtual disk. 100M stands for 100 megabytes. Of course modern operating systems take up much more than that, so it's recommended to make it at least 30 gigabytes or more, which can be done by replacing 100M with 30G. The following letters are excepted:
- K - K stands for Kilobytes. For instance, 100K would be 100 kilobytes. Unrecommended. You can create hard disk images in pure kilobytes if you wanted, e.g. 30000000k for 30 gigabytes.
- M - M stands for Megabytes. For instance, 100M would be 100 megabytes. You can also create hard disk images in pure megabytes if you want, e.g. 30000M for 30 gigabytes.
- G - G stands for Gigabytes. For instance, 100G would be 100 gigabytes.
- T - T stands for Terabytes. For instance, 1T would be 1 terabyte.
- P - P stands for Petabytes. For instance, 1P would be 1 petabyte. Unrecommended unless you happen to have a supercomputer handy.
- E - E stands for Exabytes. For instance, 1E would be 1 exabytes. Unrecommended unless you happen to have a supercomputer handy. Fun fact: The ext4 file system is capable of a maximum of 1.1529215 exabytes.
File formats[edit]
QEMU can recognize and read several different file formats, but this section will list the ones you can create with qemu-img.
qcow2[edit]
The recommended file format. It is fast, dynamically allocated, and has decent support in QEMU. Infographics – ppt templates 1 1 2 download free. However it does have a minor speed loss compared to raw, but this is unnoticeable in normal use.
qcow[edit]
This is an older version of the qcow2 file format. The main difference between the qcow2 and qcow file formats is that qcow2 supports multiple snapshots through a newer, flexible model for storing snapshots. It is recommended to use qcow2 instead.
raw[edit]
As the name suggests - it is a 'raw' file format, which means it will allocate all the space to the disk immediately, e.g. if you formatted a file named raw with 2G as the size, it would take up 2 gigabytes of space on the disk. This is the fastest option, and is recommended if you have a lot of disk space to spare.
vdi[edit]
A file format which is also compatible with VirtualBox 1.1. Recommended only if you are going to be switching through VirtualBox and QEMU frequently.
- static - If set, the image will be created with metadata preallocation.
vmdk[edit]
A file format which is compatible with VMWare 3 and 4. Recommended only if you are going to be switching through VMWare and QEMU frequently. It supports the following arguments:
- compat6 - Create a VMDK 6 image, instead of the default VMDK 4.
- hwversion - Specify the vmdk virtual hardware version. If set, the Compat6 flag cannot be enabled.
vpc[edit]
A file format which is compatible with Windows Virtual PC. Recommended only if you are going to be switching through Windows Virtual PC and QEMU frequently.
vhdx[edit]
A Hyper-V compatible image format. Not recommended unless you're going to switch between Hyper-V and QEMU frequently.
parallels[edit]
A Parallels compatible image format. Not recommended unless you're going to switch between Parallels and QEMU frequently.
file[edit]
Not a file with any format - just a plain raw file.
cow[edit]
Create Disk Image From Cd
The recommended file format. It is fast, dynamically allocated, and has decent support in QEMU. Infographics – ppt templates 1 1 2 download free. However it does have a minor speed loss compared to raw, but this is unnoticeable in normal use.
qcow[edit]
This is an older version of the qcow2 file format. The main difference between the qcow2 and qcow file formats is that qcow2 supports multiple snapshots through a newer, flexible model for storing snapshots. It is recommended to use qcow2 instead.
raw[edit]
As the name suggests - it is a 'raw' file format, which means it will allocate all the space to the disk immediately, e.g. if you formatted a file named raw with 2G as the size, it would take up 2 gigabytes of space on the disk. This is the fastest option, and is recommended if you have a lot of disk space to spare.
vdi[edit]
A file format which is also compatible with VirtualBox 1.1. Recommended only if you are going to be switching through VirtualBox and QEMU frequently.
- static - If set, the image will be created with metadata preallocation.
vmdk[edit]
A file format which is compatible with VMWare 3 and 4. Recommended only if you are going to be switching through VMWare and QEMU frequently. It supports the following arguments:
- compat6 - Create a VMDK 6 image, instead of the default VMDK 4.
- hwversion - Specify the vmdk virtual hardware version. If set, the Compat6 flag cannot be enabled.
vpc[edit]
A file format which is compatible with Windows Virtual PC. Recommended only if you are going to be switching through Windows Virtual PC and QEMU frequently.
vhdx[edit]
A Hyper-V compatible image format. Not recommended unless you're going to switch between Hyper-V and QEMU frequently.
parallels[edit]
A Parallels compatible image format. Not recommended unless you're going to switch between Parallels and QEMU frequently.
file[edit]
Not a file with any format - just a plain raw file.
cow[edit]
Create Disk Image From Cd
Ancient, depreciated QEMU file format that is not present in newer versions. Like qcow2 and qcow, it is a dynamically allocated file format. This cannot be used in Win32. Not recommended.
Read only file formats[edit]
- bochs - Bochs image file
- cloop - Linux Compressed Loop image, useful only to reuse directly compressed CD-ROM images present for example in the Knoppix CD-ROMs.
- dmg - Apple disk image
