Businesses and developers often require secure, high-performance environments for their applications. Bare metal servers provide dedicated hardware resources without the overhead of virtualization, making them ideal for resource-intensive workloads.
Private networking is one crucial feature for optimizing performance and security in bare metal environments. It allows servers within the same data center to communicate over a dedicated, isolated network, improving speed, security, and efficiency.
In this article, we’ll explore what private networking is, its benefits, how to set it up, and best practices for maintaining a secure and efficient private network.
What is Private Networking?
Private networking is an in-house, divide network where various bare metal servers in a single data center can communicate with each other without accessing the public internet. Contrary to public networks, which need to handle foreign traffic (originating from outside of your private network), a private network runs inside an isolated environment and provides:
- Faster communication – Data transfers occur over an internal network, reducing latency.
- Enhanced security – Traffic is not exposed to the public internet, minimizing attack surfaces.
- Reduced bandwidth costs – Internal data transfers typically do not count against public bandwidth limits.
Benefits of Using Private Networking
1. Improved Performance
Since private networks operate within the same data center, communication between servers is significantly faster than routing traffic through the public internet. This is especially beneficial for applications requiring low-latency connections, such as:
- High-frequency trading platforms
- Real-time analytics
- Multi-server gaming environments
2. Enhanced Security
Private networks improve your overall security by isolating your server communication from the vulnerabilities of the public internet. This reduced exposure directly mitigates several key threats, including:
- Distributed Denial of Service (DDoS) attacks: Preventing external traffic from directly reaching the internal network significantly reduces the risk of overwhelming your servers with malicious requests.
- Unauthorized access attempts: The private network's isolated nature makes it considerably harder for malicious actors outside your dedicated infrastructure to gain access to your servers.
- Data interception: Communication within the private network remains within your control, minimizing the chances of sensitive data being monitored or intercepted by external sources.
3. Cost Efficiency
Many hosting providers do not charge for internal bandwidth usage on private networks. This makes private networking a cost-effective solution for:
- Large-scale backups: Transferring substantial backup data between your servers within the private network won't incur public bandwidth charges, potentially saving significant costs.
- Data synchronization: Keeping data consistent across multiple servers for redundancy or application needs becomes more economical as the internal synchronization traffic doesn't contribute to your public bandwidth usage.
- Cluster computing: For applications utilizing multiple servers for processing power, the inter-server communication required for cluster operations benefits from free internal bandwidth, reducing overall operational expenses.
Setting Up Private Networking
Configuring private networking for bare metal servers typically involves the following steps:
Step 1: Verify Private Network Availability
- Confirm if the hosting provider supports private networking for internal server communication.
- Check whether private IPs are assigned automatically or need manual setup through the control panel or API.
Step 2:Assign Private IP Addresses
Each server in the private network should have a dedicated internal IP. These can be assigned via:
- The hosting provider’s control panel.
- DHCP within the private network.
- Manual configuration in the server’s network settings.
Step 3: Configure Network Interfaces
While /etc/network/interfaces is common on Debian-based Linux distributions, Red Hat-based systems (like CentOS and Fedora) primarily use files in /etc/sysconfig/network-scripts/ with names like ifcfg-ethX or ifcfg-ensX.
For Windows servers, the instructions are quite high-level (e.g., "configure the private IP via Network Adapter Settings"). While this is technically accurate, it would be more useful to provide a more detailed technical path.
Such as Control Panel > Network and Internet > Network and Sharing Center > Change adapter settings, then right-click the relevant network adapter, choose Properties, and configure the Internet Protocol Version 4 (TCP/IPv4) settings accordingly.
Step 4: Test Connectivity
Use tools like ping, traceroute, or iperf to verify communication between servers:
If connectivity fails, check firewall rules and routing tables.
While ping and traceroute are useful for basic connectivity, iperf is specifically designed for measuring network bandwidth and throughput, which is highly relevant for evaluating the performance benefits of a private network. It's good that it's included.
Firewall Configuration for Optimal Network Functionality
Configuring your firewall with appropriate port settings is essential for maintaining both the security and functionality of your bare metal servers within a private network. Here's an explanation of the recommended configurations:
Port 4789 (UDP/TCP): Private Communication Between Servers
This port is typically used for Virtual eXtensible Local Area Network (VXLAN), a network virtualization technology that enables the creation of overlay networks. VXLAN supports efficient and scalable communication between servers across various network segments.
Allow traffic through Port 4789 on both UDP and TCP protocols to support VXLAN, ensuring smooth and secure private communication between your servers.
SSH (Port 22): Secure Remote Management
Secure Shell (SSH) enables encrypted communication for the secure remote management of servers.
Open Port 22 only if remote management via SSH is necessary.
To improve security, consider the following:
Change the default SSH port from 22 to a non-standard port to minimize the risk of automated attacks.
Limit SSH access to specific, trusted IP addresses.
HTTP (Port 80) & HTTPS (Port 443): Web Services
These ports facilitate web traffic; Port 80 is used for HTTP, whereas Port 443 handles HTTPS, which provides encrypted and secure communication.
Open these ports if your servers are hosting web services that need to be accessible to users.
Database Ports (e.g., MySQL Port 3306): Database Access
Database servers such as MySQL communicate with client applications over designated ports, typically Port 3306.
Open database ports only between specific trusted IP addresses within your private network to prevent unauthorized access.
Best Practices for Private Networking
1. Use VLANs for Segmentation
Segment network traffic by assigning critical services (e.g., database, backup systems) to dedicated VLANs to reduce lateral movement and minimize potential attack vectors.
2. Monitor Network Traffic
Install network monitoring tools like Wireshark, Nagios, or Zabbix to detect anomalies, unauthorized access requests, or unusual traffic patterns in real time.
3. Implement Redundancy
Implement interface bonding to provide fault tolerance and maintain connectivity in case of individual network link failures.
4. Regularly Update Security Policies
Occasionally check and implement security controls such as firewall configurations, ACLs, and crypto settings to align with the latest threat profiles and regulatory requirements.
5. Document Network Layout
Keep an up-to-date network topology diagram outlining IP allocations, VLAN configurations, and server functions to support efficient troubleshooting and infrastructure scaling.
Conclusion
Private networking is a powerful feature for bare metal servers, offering improved speed, security, and cost efficiency for internal communications. By following proper setup and security best practices, businesses can optimize their infrastructure for high-performance applications while maintaining compliance with industry regulations.
Whether you're running a database cluster, a high-traffic web application, or a secure backup system, leveraging private networking ensures your servers communicate efficiently and safely.
