Provide me with a practical case configuration for Zabbix and list the relevant commands.

Certainly! Below is a practical case configuration for Zabbix, which is an open-source monitoring tool used for monitoring various network services, servers, and hardware. In this example, we'll configure Zabbix to monitor a Linux server by collecting basic system metrics like CPU, memory, disk space, and network usage.

### Prerequisites

1. **Zabbix Server Installed**: Ensure you have a Zabbix server set up and running.
2. **Zabbix Agent Installed**: Install the Zabbix agent on the Linux server you wish to monitor.

### Installation of Zabbix Server and Agent

Follow these commands to install Zabbix server and agent (example for Ubuntu):

#### Zabbix Server Installation
1. **Update Package Index:**
   ```bash
   sudo apt update
   ```

2. **Install Zabbix Server and Web Interface**:
   ```bash
   sudo apt install zabbix-server-mysql zabbix-frontend-php zabbix-agent
   ```

3. **Install MySQL Server:**
   ```bash
   sudo apt install mysql-server
   ```

4. **Create Zabbix Database:**
   ```bash
   mysql -uroot -p
   CREATE DATABASE zabbix CHARACTER SET utf8mb4 COLLATE utf8mb4_bin;
   CREATE USER 'zabbixuser'@'localhost' IDENTIFIED BY 'your_password';
   GRANT ALL PRIVILEGES ON zabbix.* TO 'zabbixuser'@'localhost';
   FLUSH PRIVILEGES;
   EXIT;
   ```

5. **Configure Database for Zabbix Server:**
   Edit the configuration file `/etc/zabbix/zabbix_server.conf`:
   ```bash
   DBPassword=your_password
   ```

6. **Initialize the Database Schema:**
   ```bash
   cd /usr/share/doc/zabbix-server-mysql/examples/ | gunzip create.sql.gz
   mysql -uzabbixuser -pyour_password zabbix < create.sql
   ```

7. **Start and Enable the Zabbix Server and Agent:**
   ```bash
   sudo systemctl start zabbix-server
   sudo systemctl enable zabbix-server
   sudo systemctl start zabbix-agent
   sudo systemctl enable zabbix-agent
   ```

#### Zabbix Frontend Configuration
Complete the web-based frontend installation by entering the URL of your Zabbix server in a web browser.

1. Open `http://your-server-ip/zabbix`
2. Follow the on-screen steps to complete the installation.

### Agent Configuration

1. **Configure Zabbix Agent**:
   Edit the `/etc/zabbix/zabbix_agentd.conf` file and set the following parameters:
   ```conf
   Server=zabbix_server_ip
   Hostname=your_monitoring_host
   ```

2. **Start and Enable Zabbix Agent**:
   ```bash
   sudo systemctl start zabbix-agent
   sudo systemctl enable zabbix-agent
   ```

### Monitoring Configuration

#### Adding the Host in Zabbix Web Interface

1. **Log into Zabbix Web Interface**.
2. Go to **Configuration -> Hosts -> Create host**.
   - **Host name**: `LinuxServer`
   - **Visible name**: `Linux Server`
   - **Groups**: Select or create a group
   - **Agent interfaces**: Create an entry for `your_monitoring_host:10050`
   - **Templates**: Link to the template `Template OS Linux`.

3. **Save the host**.

### Relevant Commands for Monitoring

You can use several Zabbix commands to interact with the server and the agent. Here are some essential commands you might find useful:

#### On the Zabbix Server:

- **Check Zabbix Server Status**:
   ```bash
   systemctl status zabbix-server
   ```

- **Check Zabbix Web Interface Logs**: (usually located at `/var/log/zabbix/zabbix_web.log`)
   ```bash
   tail -f /var/log/zabbix/zabbix_web.log
   ```

- **Zabbix Database Health**:
   ```bash
   mysqlcheck -u zabbixuser -p
   ```

#### On the Zabbix Agent:

- **Check Zabbix Agent Status**:
   ```bash
   systemctl status zabbix-agent
   ```

- **Test Zabbix Agent Configuration**:
   ```bash
   zabbix_agentd -t system.uptime
   ```

- **Start, Stop, Restart Agent**:
   ```bash
   sudo systemctl restart zabbix-agent
   ```

### Conclusion

This configuration provides a basic setup to monitor a Linux server with Zabbix, allowing for the collection of system metrics. Depending on your requirements, you can extend this setup with more templates, create custom items, alerts, and much more based on your specific use case.