In the world of networking, a server’s IP address is its identity on the internet. For many business scenarios, especially those requiring high traffic handling or providing multiple services, configuring multiple IP addresses becomes very important. This not only improves server availability and security but can also balance load and optimize service response time to some extent.

Why are multiple IP addresses needed?

There are many benefits to configuring multiple IP addresses for a server, including:

  • Load Balancing: By using different IP addresses, traffic can be distributed to different network interfaces on the server, thus balancing the load and improving efficiency.
  • Service Isolation: Different services can be bound to different IP addresses, so if one service has a problem, it will not affect the normal operation of other services.
  • Enhanced Security: Multiple IP configurations can be used to isolate public services from internal services, enhancing security.
  • Virtual Hosting: Hosting multiple websites on the same server with diffe\rent IP addresses makes it convenient for management and maintenance.

How to obtain server IP addresses?

The method of obtaining multiple IP addresses varies depending on the operating system.

For Linux systems:

ifconfig command:

Open the terminal, enter the ifconfig command, and it will list all network interfaces and their IP address information.

ip command:

Enter ip addr show to display all network interfaces and their IP address information.

Edit network configuration files:

View files such as /etc/network/interfaces or /etc/sysconfig/network-scripts/ifcfg-<interface>, which contain network interface configuration information.

For Windows systems:

PowerShell:

Open PowerShell and run the Get-NetIPAddress command to list all network interfaces and IP addresses.

ipconfig command:

Enter ipconfig at the command prompt to view all network interfaces’ IP address information.

For macOS systems:

ifconfig command:

Run the ifconfig command in the terminal to list all network interfaces and their IP addresses.

Network Preferences:

Go to the “Network” option in System Preferences and select the appropriate network interface to view its IP address.

Common methods:

Obtaining through programming languages:

You can use programming languages like Python, Bash, PowerShell, etc., to write scripts that call system APIs to obtain IP address information.

For example, using the Python socket module you can obtain it like this:

import socket
host_name = socket.gethostname()
ip_addresses = socket.gethostbyname_ex(host_name)
print(ip_addresses)

View network configuration files:

Directly view the network configuration files on the server, which contain detailed information about the system’s network configuration.