As a DevOps or Network Engineer, it's important to have a solid understanding of Linux commands. Linux is a powerful operating system that offers a wide range of tools and commands to help you manage your servers and networks efficiently. In this article, we will look at the top 36 Linux commands that every DevOps and Network Engineer should know.
Table of Contents
Introduction
File and Directory Management Commands
Text Editing Commands
Networking Commands
System Monitoring Commands
Conclusion
File and Directory Management Commands
cp
The cp
command is used to copy files and directories from one location to another. This command has many options, including the ability to preserve file permissions and ownership.
mv
The mv
command is used to move files and directories from one location to another. This command can also be used to rename files and directories.
rm
The rm
command is used to remove files and directories. It has many options, including the ability to force the removal of files and directories and the ability to delete files based on certain criteria.
mkdir
The mkdir
command is used to create new directories. It can also be used to create nested directories.
touch
The touch
command is used to create new files. It can also be used to update the modification time of existing files.
chmod
The chmod
command is used to change the permissions of files and directories. This command can be used to add or remove permissions for the owner, group, and other users.
Text Editing Commands
nano
The nano
command is a simple text editor that is easy to use for beginners. It is often used for quick edits to configuration files and scripts.
vi/vim
The vi
and vim
commands are powerful text editors that are highly customizable. They can be used for simple edits as well as complex scripting and programming.
grep
The grep
command is used to search for a specific pattern or text string in a file. It can be used to quickly find information in log files or configuration files.
sed
The sed
command is used to perform text manipulation on a file. It can be used to replace text, delete lines, or perform other complex text operations.
awk
The awk
command is used to process text files and perform complex operations on them. It can be used to extract information from log files or perform other data processing tasks.
Networking Commands
ping
The ping
command is used to test the connectivity of a network device. It sends an ICMP echo request to the device and waits for a response.
traceroute
The traceroute
command is used to trace the route that a packet takes through a network. It can be used to diagnose network connectivity issues.
netstat
The netstat
command is used to display information about active network connections, open ports, and listening services on a server.
nmap
The nmap
command is a powerful network scanner that can be used to discover devices on a network, scan for open ports, and detect vulnerabilities.
dig
The dig
command is used to query DNS servers for information about a domain name. It can be used to test DNS resolution and diagnose DNS issues.
ifconfig/ip
The ifconfig
and ip
commands are used to display and configure network interfaces on a server or device. They can be used to configure network settings, troubleshoot network issues, and monitor network activity.
nslookup
The nslookup
commands are used to query Domain Name System (DNS) servers to obtain a domain name or IP address mapping information. It is commonly used to diagnose and troubleshoot DNS-related issues, and can also be used to verify DNS records and identify network connectivity issues.
ss
The ss
commands are used to display detailed information about active network connections, listening sockets, and network statistics. It is used to monitor and troubleshoot network-related issues, and is particularly useful for advanced users and system administrators
tcpdump
The tcpdump
is a command-line packet analyzer that captures and displays network packets in real time. It is used to analyze network traffic, diagnose network-related issues, and troubleshoot network problems
iftop
The iftop
is a command-line network monitoring tool that displays real-time bandwidth usage of network interfaces. It is used to identify network traffic patterns and monitor network activities
whois
The whois
is a command-line tool that retrieves information about a domain name, such as the domain registrar, creation and expiration date, and the nameservers associated with it. It is used by system administrators, network engineers, and security professionals to perform various tasks like investigating domain ownership and identifying potential domain-related issues
ssh
The ssh
command is used to remotely connect to a server or device using the SSH protocol. It provides a secure and encrypted connection that can be used to perform command-line operations or run graphical applications remotely.
scp
The scp
command is used to securely copy files between servers or local and remote directories using the SSH protocol. It can be used to transfer files between systems without the need for additional software or services.
rsync
The rsync
command is used to synchronize files and directories between servers or local and remote directories. It can be used to efficiently transfer large amounts of data and keep files up-to-date across multiple systems.
curl
The curl
command is used to transfer data to or from a server using various protocols like HTTP, FTP, IMAP, SMTP, etc. It can be used to download files, upload data, and perform other actions related to data transfer.
wget
The wget
command is used to download files from the web using HTTP, HTTPS, and FTP protocols. It provides a simple way to download entire websites, recursively download files, and resume interrupted downloads.
System Monitoring Commands
top
The top
command is used to display real-time information about system processes and resource usage. It can be used to identify processes that are consuming a lot of resources.
htop
The htop
command is a more advanced version of the top
command that provides additional features and a more user-friendly interface. It can be used to monitor system processes and resource usage in real-time.
ps
The ps
command is used to display information about running processes on a system. It can be used to identify the process
df
The df
command is used to display information about disk space usage on a server. It can be used to identify disks that are running low on space.
du
The du
command is used to display information about the disk usage of files and directories on a system. It can be used to check the size of individual files or directories.
free
The free
command is used to display information about system memory usage. It can be used to identify processes that are consuming a lot of memory.
service/systemctl
The service
and systemctl
commands are used to manage system services on a Linux system. They can be used to start, stop, or restart services, as well as to check the status of running services.
crontab
The crontab
command is used to schedule and automate recurring tasks on a Linux system. It can be used to run scripts or commands at specific times or intervals.
apt/yum
The apt
and yum
commands are used to manage software packages on a Linux system. They can be used to install, update, or remove packages, as well as to check for available updates.
Conclusion
In conclusion, these 36 Linux commands are essential for any DevOps or Network Engineer. Mastering these commands will allow you to efficiently manage your servers and networks, troubleshoot issues, and improve system performance.