# Knight Online Login Server - Linux Version

This directory contains the Linux-compatible version of the Knight Online Login Server.

## Prerequisites

Before building and running the Login Server on Linux, make sure you have the following dependencies installed:

### Ubuntu/Debian
```bash
sudo apt-get update
sudo apt-get install build-essential cmake g++ unixodbc-dev
```

### CentOS/RHEL/Fedora
```bash
# CentOS/RHEL
sudo yum groupinstall "Development Tools"
sudo yum install cmake unixODBC-devel

# Fedora
sudo dnf groupinstall "Development Tools"
sudo dnf install cmake unixODBC-devel
```

## Building the Server

### Quick Start
```bash
# Make build script executable
chmod +x build.sh

# Build everything
./build.sh all
```

### Manual Build Steps
```bash
# 1. Make scripts executable
chmod +x build.sh loginserver.sh

# 2. Build the project
./build.sh build

# 3. Install binaries
./build.sh install
```

### Build Options
```bash
./build.sh clean          # Clean build files
./build.sh build          # Build project
./build.sh rebuild        # Clean and build
./build.sh install        # Install binaries
./build.sh all            # Full build and install
./build.sh -j 4 build     # Build with 4 parallel jobs
```

## Configuration

### Database Setup
1. Install and configure your ODBC driver for your database
2. Edit `LogIn.ini` with your database connection details:

```ini
[ODBC]
DSN=KO_MAIN
UID=your_username
PWD=your_password
```

### Server Configuration
Edit `LogIn.ini` to configure server settings:

```ini
[SETTINGS]
PORT=15100

[SERVER_LIST]
COUNT=1
SERVER_00=192.168.1.104
LANIP_00=192.168.1.104
NAME_00=Your Server Name
ID_00=1
```

## Running the Server

### Start the Server
```bash
./loginserver.sh start
```

### Check Server Status
```bash
./loginserver.sh status
```

### View Server Logs
```bash
./loginserver.sh logs
```

### Stop the Server
```bash
./loginserver.sh stop
```

### Restart the Server
```bash
./loginserver.sh restart
```

## Management Commands

The `loginserver.sh` script provides several management commands:

- `start` - Start the login server
- `stop` - Stop the login server  
- `restart` - Restart the login server
- `status` - Show server status and process information
- `logs` - View server logs in real-time
- `config` - Create default configuration file

## File Structure

```
LoginServer/
├── bin/                    # Compiled binaries
│   └── LoginServer        # Main server executable
├── build/                 # CMake build directory
├── Logs/                  # Server log files
│   ├── LoginServer.log    # Main server log
│   ├── Login_DD_MM_YYYY.log # Daily user login log
│   └── server_output.log  # Server console output
├── build.sh              # Build script
├── loginserver.sh         # Server management script
├── LogIn.ini             # Server configuration
├── CMakeLists.txt        # CMake configuration
└── README_LINUX.md       # This file
```

## Troubleshooting

### Common Issues

#### 1. Build Failures
- Make sure all dependencies are installed
- Check that you have sufficient permissions
- Verify CMake version (3.10 or higher required)

#### 2. ODBC Connection Issues
```bash
# Test ODBC connection
isql -v DSN_NAME username password

# List available ODBC drivers
odbcinst -q -d

# List configured DSNs
odbcinst -q -s
```

#### 3. Permission Issues
```bash
# Make scripts executable
chmod +x build.sh loginserver.sh

# Check binary permissions
chmod +x bin/LoginServer
```

#### 4. Port Already in Use
```bash
# Check what's using the port
sudo netstat -tlnp | grep :15100

# Kill process using the port
sudo kill -9 PID
```

### Debugging

#### Enable Debug Mode
Edit CMakeLists.txt and add debug flags:
```cmake
set(CMAKE_BUILD_TYPE Debug)
set(CMAKE_CXX_FLAGS_DEBUG "-g -O0 -DDEBUG")
```

#### Run with GDB
```bash
gdb ./bin/LoginServer
(gdb) run
```

#### Monitor System Resources
```bash
# Monitor server process
top -p $(cat loginserver.pid)

# Check memory usage
cat /proc/$(cat loginserver.pid)/status

# Monitor network connections
ss -tlnp | grep LoginServer
```

## Security Considerations

1. **Firewall Configuration**
   ```bash
   # Allow login server port
   sudo ufw allow 15100/tcp
   ```

2. **User Permissions**
   - Run the server as a non-root user
   - Set appropriate file permissions
   - Use a dedicated service user

3. **Database Security**
   - Use strong database passwords
   - Limit database user permissions
   - Enable database connection encryption

## Integration with Gitea

This server is configured to work with the Gitea repository at:
- Local: `http://192.168.1.104:3000/`
- SSH: `ssh://gitea@192.168.1.104:2222/leventferrah/knightonline.git`

### Deployment Workflow
```bash
# Pull latest changes
git pull knight main

# Build and deploy
./build.sh all

# Restart server
./loginserver.sh restart
```

## Performance Tuning

### System Limits
Edit `/etc/security/limits.conf`:
```
username soft nofile 65536
username hard nofile 65536
```

### Network Optimization
Edit `/etc/sysctl.conf`:
```
net.core.somaxconn = 1024
net.ipv4.tcp_max_syn_backlog = 1024
```

## Monitoring

### Log Monitoring
```bash
# Monitor all logs
tail -f Logs/*.log

# Monitor specific log
tail -f Logs/LoginServer.log
```

### Process Monitoring
```bash
# Check if server is running
./loginserver.sh status

# Monitor resource usage
watch -n 1 './loginserver.sh status'
```

## Support

For issues and support:
- Check the server logs in `Logs/` directory
- Verify configuration in `LogIn.ini`
- Test database connectivity
- Check network connectivity and firewall settings

## Version Information

- **Server Version**: Knight Online Login Server v1.0
- **Platform**: Linux (Ubuntu/CentOS/Debian compatible)
- **Build System**: CMake 3.10+
- **Compiler**: GCC 7+
- **Dependencies**: ODBC, pthread