In openSUSE Linux, you can use various commands to read and analyze logs or log files. Here are some of the most commonly used commands: less: This command allows you to view the contents of a log file and navigate through it. For example, to view the /var/log/messages file, you can run: less /var/log/messages To … Read more
To print the line after a pattern match in awk, you can use a flag variable to keep track of whether the current line matches the pattern, and print the next line if the flag is set. Here’s an example: Suppose we have a file called data.txt with the following content: apple banana cherry date … Read more
If you are testing PF firewall configuration on a remote server over an SSH session, it is important to have a way to automatically reset the firewall in case something goes wrong and you lose your connection to the server. One way to do this is to use a script that runs periodically and resets … Read more
Yum-cron is a package that can be used to automatically update packages on RHEL/CentOS Linux systems. Here are the steps to set up yum-cron: Install yum-cron: sudo yum install yum-cron Edit the configuration file for yum-cron: sudo vi /etc/yum/yum-cron.conf The configuration file has several options that can be used to customize the behavior of yum-cron. … Read more
AIDE (Advanced Intrusion Detection Environment) is a popular and powerful tool for monitoring file system changes on a Linux system. It can be used to detect and alert on any unauthorized changes to files, directories, and other system objects. Here are the steps to install and configure AIDE on Debian and Ubuntu Linux systems: Install … Read more
To run a crontab job every minute on a Linux or Unix-like system, you can use the following syntax: * * * * * command-to-be-executed This will run the command-to-be-executed every minute of every hour of every day of the week. Here’s a breakdown of what each * represents: * in the first field represents … Read more
The networking performance of a Linux system can be improved by tuning the network stack buffers sizes. The buffer sizes can be adjusted using the sysctl command. Here are the steps to tune the network stack buffers size: Open a terminal or shell prompt on your Linux system. Verify that the net.core.rmem_max, net.core.wmem_max, net.ipv4.tcp_rmem, and … Read more
You can verify an SSL certificate from a shell prompt using the openssl command-line tool. Here’s how to do it: Open a terminal or shell prompt on your Linux or Unix system. Run the following command to check the SSL certificate of a website: openssl s_client -connect example.com:443 Replace example.com with the domain name or … Read more
In Linux, you can limit the CPU usage of a process by using the cpulimit command. Here’s how to use it: Install cpulimit on your Linux system, if it is not already installed. You can do this using your distribution’s package manager. For example, on Ubuntu or Debian, you can run: sudo apt-get install cpulimit … Read more
To add a swap file in Solaris or OpenSolaris, follow these steps: Determine the size of the swap file that you want to create. The size of the swap file should be at least as large as the amount of RAM installed on the system. For example, if you have 1GB of RAM, you may … Read more