How to configure highly available port forwarding on Linux

How to configure high-availability port forwarding on Linux

1. Background overview
In the architecture of distributed systems, port forwarding is a very common network technology. Through port forwarding, connection requests from the external network can be forwarded to internal nodes, thereby achieving high availability and load balancing of external services. On the Linux operating system, we can use some tools and configurations to achieve high-availability port forwarding. This article will introduce in detail how to configure and manage high-availability port forwarding using the Linux operating system.

2. Use iptables to implement port forwarding
iptables is a commonly used firewall software on Linux systems and can also be used to implement port forwarding functions. The following is an example of using iptables to implement port forwarding:

1. First, you need to confirm that the iptables software has been installed on the system. Execute the following command on the terminal:

sudo apt-get install iptables

2. Set port forwarding rules. Assume that we need to forward the access request from the public network IP to a node on the intranet. You can use the following command to configure port forwarding:

sudo iptables -A PREROUTING -t nat -i eth0 -p tcp --dport 80 -j DNAT --to 192.168.0.10:80
sudo iptables -A FORWARD -p tcp -d 192.168.0.10 --dport 80 -m state --state NEW,ESTABLISHED,RELATED -j ACCEPT

where eth0 is External network interface, 192.168.0.10 is the IP address of the internal network node, 80 is the port number that needs to be forwarded.

3. Save configuration. When the above configuration is completed, we need to save the configuration to the iptables configuration file so that the configuration can be automatically loaded after the system restarts. Execute the following command to save the configuration:

sudo sh -c "iptables-save > /etc/iptables.rules"

4. Add a self-starting script. In order to make the configuration automatically loaded when the system starts, we can create a self-starting script and add it to the system's startup service. Create a script named iptables.sh with the following content:

#!/bin/sh
/sbin/iptables-restore < /etc/iptables.rules

Save the script to the /etc/init.d directory and set it as the script Add execution permissions:

sudo chmod +x /etc/init.d/iptables.sh

Then, add the script to the startup service:

sudo update-rc.d iptables.sh defaults 99

At this point, we have completed the configuration of using iptables to implement port forwarding.

3. Use HAProxy to achieve high-availability port forwarding
In addition to using iptables, we can also use HAProxy to achieve high-availability port forwarding. HAProxy is a reliable, high-performance load balancing software suitable for port forwarding needs in distributed systems. The following is an example of using HAProxy to configure high-availability port forwarding:

1. First, you need to confirm that the HAProxy software has been installed on the system. Execute the following command on the terminal:

sudo apt-get install haproxy

2. Edit the HAProxy configuration file. Open the configuration file /etc/haproxy/haproxy.cfg and add the following content:

frontend http-in
     bind *:80
     default_backend backend_servers

backend backend_servers
     balance roundrobin
     server server1 192.168.0.10:80 check
     server server2 192.168.0.11:80 check

Among them, 192.168.0.10 and 192.168.0.11 is the IP address of the internal node, 80 is the port number that needs to be forwarded.

3. Restart the HAProxy service. Execute the following command to restart the HAProxy service:

sudo service haproxy restart

At this time, HAProxy will forward the access request to the internal node according to the rules in the configuration file to achieve high-availability port forwarding.

4. Summary
This article introduces the method of configuring high-availability port forwarding on the Linux operating system, using iptables and HAProxy as examples. In actual applications, we can choose the appropriate method for configuration and deployment according to specific needs. By rationally using port forwarding, the reliability and load capacity of the system can be improved, and more stable and efficient services can be provided.

The above is the detailed content of How to configure highly available port forwarding on Linux. For more information, please follow other related articles on the PHP Chinese website!