In Linux or Unix, you can use the sort command to sort a specific field or column in a text file. The sort command sorts the input lines in a specified order, and you can control the sort order by specifying options. Here’s an example to sort a file by the third field or column: … Read more

To install nmap on a Debian Linux 9/10/11 system, you need to use the package manager apt. Here’s the process to install nmap: Update the package index: sudo apt update Install nmap: sudo apt install nmap This will install nmap and any other packages it depends on. After the installation is complete, you can use … Read more

In Python, you can use the os.path.isfile() function to check if a file exists. The os.path.isfile() function takes a file path as its argument and returns True if the file exists and is a regular file, and False otherwise. Here’s an example: import os.path file_path = ‘/path/to/file.txt’ if os.path.isfile(file_path): print(f'{file_path} exists and is a file.’) … Read more

The grep command is used to search for a pattern in a file or files. To display the line numbers along with the matching lines, you can use the -n option. Here’s an example: grep -n ‘pattern’ file.txt In this example, pattern is the string you’re searching for, and file.txt is the file you’re searching … Read more

In Linux or Unix, you can use the ls command to show the directory listing. The ls command lists the files and directories in a specified directory. By default, it lists the contents of the current directory. Here are some common options that can be used with the ls command: -l: Display the listing in … Read more

To run fsck on a LUKS (dm-crypt) based LVM physical volume, you need to follow these steps: Unlock the LUKS partition: First, you need to unlock the LUKS partition to access the LVM physical volume. You can do this by running the following command: sudo cryptsetup luksOpen /dev/<device> <luks_mapper_name> Replace <device> with the actual device … Read more

There are several ways to find the OS version in Ubuntu Linux: Using the lsb_release command: This command provides information about the Linux Standard Base (LSB) and the version of Ubuntu that you’re running. To use it, run the following command in your terminal: lsb_release -a Using the /etc/os-release file: This file contains information about … Read more

To delete a user on a Linux system, you can use the userdel command. Here’s the basic syntax for using the userdel command: userdel <username> For example, if you want to delete the user john, you would run the following command: sudo userdel john Note that by default, the userdel command only removes the user … Read more

htop is a popular process monitoring tool for Linux that provides a more user-friendly and interactive way of monitoring system processes than the standard top utility. Here’s how you can install htop on CentOS or RHEL: Update the package index: Before installing any new packages, you should always update the package index on your system. … Read more

The “Neighbour Table Overflow” error in Linux can occur when the system’s neighbor cache table, which is used to store information about network neighbors such as ARP cache entries, has become full. This can result in network connectivity issues and may cause other problems, such as high network latency or dropped packets. Here are a … Read more