Port knocking is a security technique used to hide services on a network behind a firewall until a specific sequence of connection attempts (knocks) is received. To set up port knocking on Debian or Ubuntu, you will need to install two components: knockd, which acts as the daemon that listens for knocks and opens the … Read more
To uninstall the Apache (HTTPD) server on CentOS or Red Hat Enterprise Linux (RHEL) 5/6, you can use the following steps: Stop the Apache service: service httpd stop Remove the Apache packages: yum remove httpd This will remove the Apache packages and all of its dependencies from your system. Remove any leftover Apache configuration files: … Read more
The dig command can be used to find out the Time to Live (TTL) value for DNS records. The TTL value is the amount of time in seconds that a DNS record will be cached on a local DNS resolver before it needs to be refreshed. Here’s how you can use the dig command to … Read more
The “WARNING: Duplicate VG name server1 LVM2” error occurs when you have multiple Logical Volume Manager (LVM) volume groups with the same name on your Linux system. To resolve this error, you will need to remove the duplicate volume group. Here’s how: Run the vgs command to list all of the volume groups on your … Read more
To find and delete all hidden directories (directories starting with a dot) in a Linux or Unix system, you can use the following command: find /path/to/search -name “.*” -type d -exec rm -rf {} \; Replace /path/to/search with the path to the directory where you want to search for hidden directories. For example, to find … Read more
To upgrade from Debian 6.0.x (Squeeze) to 7.0.0 (Wheezy), you can follow these steps: Backup your data: Before upgrading, it’s always a good idea to backup your data to ensure that you don’t lose any important files during the upgrade process. Update your current installation: Run the following commands to update your current Debian Squeeze … Read more
To install a Wake-on-LAN client on an Ubuntu Linux server, you can use the etherwake package. Here’s how to install it: Open a terminal window. Install the etherwake package by running the following command: sudo apt-get install etherwake After the installation is complete, you can use the etherwake command to send a Wake-on-LAN packet to … Read more
To install Google Chrome browser on an Ubuntu Linux system, you can use the following steps: Download the Google Chrome Debian package by visiting the following link: https://www.google.com/chrome/ Open a terminal window and navigate to the directory where you downloaded the package. Install the package by running the following command: sudo dpkg -i google-chrome-stable_current_amd64.deb Note: … Read more
To use scp on a Linux or Unix system and avoid overwriting an existing file, you can use the -n or –no-clobber option. This option prevents scp from overwriting existing files in the target directory. Here’s an example of using scp with the -n option: scp -n source_file user@target_host:target_directory In this example, source_file is the … Read more
To control the fan speed and get the CPU temperature on a Dell laptop running Linux, you can use the lm-sensors and fancontrol packages. Here are the steps to install and configure them: Install the lm-sensors and fancontrol packages by running the following command in the terminal: sudo apt-get install lm-sensors fancontrol Run the following … Read more