Rahul Sahu

To delete a single command from the history in a Linux/Unix Bash shell, you can use the “history” command to view the command history, and then use the “history -d” command to delete a specific command by its number. Here’s an example: View the command history using the “history” command: history Find the number of … Read more

To change the system’s hostname on HP-UX, you can use the “sam” command-line utility. The “sam” utility is the System Administration Manager, which provides a text-based interface for managing various system configurations, including the hostname. Here’s how you can change the hostname using the “sam” utility: Log in as the superuser (root) Open the “sam” … Read more

To find the CPU temperature in FreeBSD, you can use the sysctl command to retrieve the temperature information from the system’s sensors. The temperature is stored in the “hw.sensors.cpu0.temp0” sysctl node. Example: sysctl hw.sensors.cpu0.temp0 Output: hw.sensors.cpu0.temp0=56.0 degC Note: The temperature output may vary depending on your system and the type of sensor used. The above … Read more

To check the boot partition in Linux, you can use the “lsblk” command. This command lists all the available block devices and their respective partitions. The boot partition is typically the root partition (/) and is mounted as the root file system. The output of the command will show the name of the partition (e.g., … Read more

You can list all iptables rules with line numbers in Linux using the following command: sudo iptables -nL –line-numbers The -n option specifies that IP addresses and port numbers should be displayed in numeric format, rather than in reverse DNS format. The -L option lists all the rules in the specified table (the filter table, … Read more

You can undefine and unset a bash environment variable using the unset command in the terminal. For example, if you have an environment variable named MY_VAR, you can undefine and unset it by running the following command: unset MY_VAR After running this command, the variable MY_VAR will no longer be defined, and any attempt to … Read more

There are several ways to check the operating system version in the Linux command line. Here are a few common methods: Using the lsb_release command: lsb_release -a This command displays detailed information about the Linux distribution, including the version, release number, and codename. Using the /etc/os-release file: cat /etc/os-release This file contains information about the … Read more

The upower command is a tool in Linux for monitoring and managing power usage on the system. It provides information about the state of the battery, the power supply, and other power-related information. Here are some common examples of how to use the upower command: Get a list of all power devices on the system: … Read more

In Fedora Linux, you can list the services that run at boot time using the systemctl command. The systemctl command is used to control the system manager, which is responsible for starting and stopping services and managing the system’s state. To list all services that start at boot time in Fedora, run the following command: … Read more

To find out when a package was installed or updated on a Debian or Ubuntu system, you can use the dpkg command in the terminal. The dpkg command provides information about the packages installed on your system, including the installation date and time. To see the installation date of a specific package, run the following … Read more