Logstash is an open-source data processing pipeline that allows you to collect, transform, and store data from various sources in real-time. It is part of the Elastic Stack, which also includes Elasticsearch for searching and analyzing data, and Kibana for visualizing and exploring data. To install Logstash on CentOS 7, you can follow the steps below: 1. Update your system: ``` sudo yum update ``` 2. Install Java Development Kit (JDK): ``` sudo yum install java-1.8.0-openjdk-devel ``` 3. Import the Elastic GPG key: ``` sudo rpm --import https://artifacts.elastic.co/GPG-KEY-elasticsearch ``` 4. Create a Logstash repository file: ``` sudo nano /etc/yum.repos.d/logstash.repo ``` Add the following content to the file: ```html [logstash-7.x] name=Elastic repository for Logstash baseurl=https://artifacts.elastic.co/packages/7.x/yum gpgcheck=1 gpgkey=https://artifacts.elastic.co/GPG-KEY-elasticsearch enabled=1 autorefresh=1 type=rpm-md ``` 5. Save the file and exit the editor. 6. Install Logstash: ``` sudo yum install logstash ``` 7. Once the installation is complete, you can start the Logstash service: ``` sudo systemctl start logstash ``` 8. To enable Logstash to start on system boot, run: ``` sudo systemctl enable logstash ``` Logstash is now installed and running on your CentOS 7 system. You can configure Logstash to collect data from various sources, perform transformations, and send the processed data to Elasticsearch or other output destinations. Please note that Logstash is a powerful tool and requires careful configuration to suit your specific use case. It is recommended to refer to the official Logstash documentation for detailed instructions on configuring and using Logstash effectively.