Geographic Load Distribution

High-traffic websites often serve global audiences, requiring geographic distribution strategies that optimize both performance and security.
Anycast Firewall Deployment: Implement anycast routing for distributed firewall presence:
# Anycast health check and announcement manager
import subprocess
import requests
import time

class AnycastManager:
    def __init__(self, anycast_ip, health_check_url):
        self.anycast_ip = anycast_ip
        self.health_check_url = health_check_url
        self.bird_config = "/etc/bird/bird.conf"
        
    def check_health(self):
        """Verify local services are healthy"""
        
        try:
            # Check firewall service
            fw_status = subprocess.run(['systemctl', 'is-active', 'firewall'], 
                                     capture_output=True, text=True)
            if fw_status.stdout.strip() != 'active':
                return False
            
            # Check web service
            response = requests.get(self.health_check_url, timeout=5)
            if response.status_code != 200:
                return False
                
            # Check system resources
            load_avg = os.getloadavg()[0]
            cpu_count = os.cpu_count()
            if load_avg > cpu_count * 2:  # System overloaded
                return False
                
            return True
            
        except Exception as e:
            print(f"Health check failed: {e}")
            return False
    
    def update_bgp_announcement(self, announce=True):
        """Update BGP announcements based on health"""
        
        if announce:
            # Announce anycast IP
            bird_command = f"""
protocol static anycast_routes {{
    route {self.anycast_ip}/32 blackhole;
}}
"""
        else:
            # Withdraw anycast IP
            bird_command = f"""
protocol static anycast_routes {{
    # route {self.anycast_ip}/32 blackhole;
}}
"""
        
        # Update BIRD configuration
        with open(self.bird_config, 'w') as f:
            f.write(bird_command)
            
        # Reload BIRD
        subprocess.run(['birdc', 'configure'])
    
    def run(self):
        """Main monitoring loop"""
        
        consecutive_failures = 0
        announced = True
        
        while True:
            if self.check_health():
                consecutive_failures = 0
                if not announced:
                    print("Health restored, announcing anycast IP")
                    self.update_bgp_announcement(True)
                    announced = True
            else:
                consecutive_failures += 1
                if consecutive_failures >= 3 and announced:
                    print("Health check failed, withdrawing anycast IP")
                    self.update_bgp_announcement(False)
                    announced = False
            
            time.sleep(10)  # Check every 10 seconds