Using the dd command in Linux-LINUX-php.cn

Home

System Tutorial

LINUX

Using the dd command in Linux

WBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWB

Feb 18, 2024 pm 09:20 PM

linuxusagedata lostdd command

Usage and code examples of the dd command in Linux

1. Command introduction
The dd command is a powerful disk copy command in the Linux system. It can copy an input file to an output file and copy it according to the Format conversion is required. It can be used to create image files, backup and restore disk data, clone disk partitions, etc. The dd command is very powerful, but it is also very dangerous because it can directly read and write disk operations without confirmation, so you should be very careful when using it.

2. Common usage and code examples

Copy disk partition
The following is an example of copying one disk partition to another disk partition. Assume that /dev/sda1 is the source partition and /dev/sdb1 is the target partition.
```
dd if=/dev/sda1 of=/dev/sdb1 bs=4M conv=notrunc,noerror
```
Explanation:
if: input file, that is, the source partition
of: output file, that is, the target partition
bs: block size , used to specify the block size of read and write operations, here set to 4M
conv: used to specify format conversion options, here use notrunc and noerror
- notrunc: no Truncate the output file; that is, if the output file is shorter than the input file, the output file will not be truncated, but will be written directly to the end of the file
- noerror: Do not stop the operation when an error occurs and continue execution
Create a blank image file
The following is an example of creating a blank image file. Create a blank image file with a size of 1GB as image.img.
```
dd if=/dev/zero of=image.img bs=1M count=1024
```
Explanation:
if: Input file, that is, /dev/zero. In Linux, /dev/zero is a special device file. When reading, it will return a string of characters all 0
of: output file, that is, image.img
bs: block Size, used to specify the block size for read and write operations, here set to 1M
count: The number of blocks to copy, here set to 1024, that is, copy 1GB of data
Create a disc Image file
The following is an example of copying the contents of a CD to an image file. Assuming that the CD device is /dev/sr0, copy the CD content to isoimage.iso.
```
dd if=/dev/sr0 of=isoimage.iso bs=2048
```
Explanation:
if: input file, i.e. CD device/dev/sr0
of: output file, i.e. isoimage.iso
bs: block size, used to specify the block size for read and write operations, here set to 2048
Restore image files to disk partitions
The following is a method to restore image files to a disk partition Example. Assume that the image file is image.img, restore to the target partition /dev/sdc1.
```
dd if=image.img of=/dev/sdc1 bs=4M conv=notrunc,noerror
```
Explanation:
if: input file, that is, the image file image.img
of: output file, that is, the target partition /dev/sdc1
bs: block size, used to specify the block size for read and write operations, here set to 4M
conv: used to specify format conversion options, here use notrunc and noerror

The above are some common usages and code examples of the dd command. In actual use, parameters need to be adjusted according to specific needs. At the same time, because the operation of the dd command is dangerous, please use it with caution, ensure that the operation object is correct and back up important data to prevent data loss.

The above is the detailed content of Using the dd command in Linux. For more information, please follow other related articles on the PHP Chinese website!

Statement

The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

What are the main tasks of a Linux system administrator?Apr 19, 2025 am 12:23 AM

The main tasks of Linux system administrators include system monitoring and performance tuning, user management, software package management, security management and backup, troubleshooting and resolution, performance optimization and best practices. 1. Use top, htop and other tools to monitor system performance and tune it. 2. Manage user accounts and permissions through useradd commands and other commands. 3. Use apt and yum to manage software packages to ensure system updates and security. 4. Configure a firewall, monitor logs, and perform data backup to ensure system security. 5. Troubleshoot and resolve through log analysis and tool use. 6. Optimize kernel parameters and application configuration, and follow best practices to improve system performance and stability.

Is it hard to learn Linux?Apr 18, 2025 am 12:23 AM

Learning Linux is not difficult. 1.Linux is an open source operating system based on Unix and is widely used in servers, embedded systems and personal computers. 2. Understanding file system and permission management is the key. The file system is hierarchical, and permissions include reading, writing and execution. 3. Package management systems such as apt and dnf make software management convenient. 4. Process management is implemented through ps and top commands. 5. Start learning from basic commands such as mkdir, cd, touch and nano, and then try advanced usage such as shell scripts and text processing. 6. Common errors such as permission problems can be solved through sudo and chmod. 7. Performance optimization suggestions include using htop to monitor resources, cleaning unnecessary files, and using sy

What is the salary of Linux administrator?Apr 17, 2025 am 12:24 AM

The average annual salary of Linux administrators is $75,000 to $95,000 in the United States and €40,000 to €60,000 in Europe. To increase salary, you can: 1. Continuously learn new technologies, such as cloud computing and container technology; 2. Accumulate project experience and establish Portfolio; 3. Establish a professional network and expand your network.

What is the main purpose of Linux?Apr 16, 2025 am 12:19 AM

The main uses of Linux include: 1. Server operating system, 2. Embedded system, 3. Desktop operating system, 4. Development and testing environment. Linux excels in these areas, providing stability, security and efficient development tools.

Does the internet run on Linux?Apr 14, 2025 am 12:03 AM

The Internet does not rely on a single operating system, but Linux plays an important role in it. Linux is widely used in servers and network devices and is popular for its stability, security and scalability.

What are Linux operations?Apr 13, 2025 am 12:20 AM

The core of the Linux operating system is its command line interface, which can perform various operations through the command line. 1. File and directory operations use ls, cd, mkdir, rm and other commands to manage files and directories. 2. User and permission management ensures system security and resource allocation through useradd, passwd, chmod and other commands. 3. Process management uses ps, kill and other commands to monitor and control system processes. 4. Network operations include ping, ifconfig, ssh and other commands to configure and manage network connections. 5. System monitoring and maintenance use commands such as top, df, du to understand the system's operating status and resource usage.

Boost Productivity with Custom Command Shortcuts Using Linux AliasesApr 12, 2025 am 11:43 AM

Introduction Linux is a powerful operating system favored by developers, system administrators, and power users due to its flexibility and efficiency. However, frequently using long and complex commands can be tedious and er

What is Linux actually good for?Apr 12, 2025 am 12:20 AM

Linux is suitable for servers, development environments, and embedded systems. 1. As a server operating system, Linux is stable and efficient, and is often used to deploy high-concurrency applications. 2. As a development environment, Linux provides efficient command line tools and package management systems to improve development efficiency. 3. In embedded systems, Linux is lightweight and customizable, suitable for environments with limited resources.

See all articles