Deprecated Linux Networking Commands and Their Replacements

Linux is a very popular operating system among developers and system administrators due to its strong and robust command-line interface (CLI). However, some of the networking commands have become outdated over time, making way for newer and more efficient options. In this article, we'll have a look at some of the deprecated commands and their new modern-day replacements to help you keep up with your Linux networking configurations.

In this tutorial, we'll go through each of the deprecated commands and their corresponding substitutions. We'll also provide examples of how to use the new commands. By the end of this article, you'll have a clear understanding of the new networking commands in Linux systems. So, let's explore the world of deprecated Linux networking commands and their replacements together.

Deprecated Linux Networking Commands and Their Replacements

1. ifconfig → ip

`ifconfig` was a commonly used command for network configuration, but it has been deprecated and replaced with the more powerful `ip` command.

`ifconfig` was used to view and configure network interfaces and display their configurations. However, it had a number of limitations and security problems that made it unreliable. As a result, the new `ip` command was introduced, which is more powerful and flexible than the `ifconfig` command.

The `ip` command is a powerful tool that is used for network management on Linux systems. It allows a user to view and configure various aspects of network interfaces and routing tables.

Here's an example of how to use the `ip` command to view the configurations of the network interfaces −

$ sudo ip addr show

This output of the above command will display the configurations of all the network interfaces, similar to the `ifconfig` command. It will show the IP addresses, MAC addresses, and other details for each interface.

2. route → ip route

The `route` command was used to view and configure the kernel routing table in a Linux machine. However, it has been deprecated and replaced with the `ip route` command.

The `ip route` command is much more powerful and adaptable than the `route` command, and it can configure routing tables in more refined ways. With this command, you can view the contents of the routing table, add or delete routes, and modify various routing-related settings.

Here is an example of how to use the `ip route` command −

$ sudo ip route show

This command is going to display the kernel routing table and its configurations. This routing table shows how packets should be forwarded between different networks based on their destination IP addresses.

3. arp → ip neigh

The `arp` command was used to display and modify the Address Resolution Protocol (ARP) cache. However, it has been deprecated and replaced with the `ip neigh` command.

The `ip neigh` command provides similar functionality to the arp command but has some additional features. It is used to view and manage the kernel's ARP cache, which stores information about other network devices on the same network segment.

Here is an example of how to use the `ip neigh` command to display the ARP cache −

ip neigh show

The `ip neigh show` command will specifically show the contents of the ARP cache, including the IP address, MAC address, and interface information for each device in the cache.

4. netstat → ss

The `netstat` command was commonly used to display network connections, routing tables, and interface statistics in Linux systems. However, it has been deprecated and replaced with the new `ss` command.

The `ss` command (short for "socket statistics") is a Linux utility that is used to display detailed information about the network sockets and connections. It is more efficient and faster than `netstat`, and it provides more detailed information about network connections.

Here is an example of how to use the `ss` command −

$ sudo ss -tunap

This output of the above command will display information about all TCP and UDP sockets, including their state and associated processes, as well as the local and remote addresses.

5. iptables → nftables

The `iptables` command was used to configure firewall rules and packet filtering in Linux. However, it has been deprecated and replaced with the `nftables` command.

`nftables` is a Linux command-line utility used for managing the Linux kernel's packet filtering framework. It is a modern replacement for the older `iptables` firewall system and offers enhanced performance, scalability, and ease of use.

With `nftables`, you can define rules for filtering network traffic based on a variety of criteria, such as source and destination IP addresses, TCP/UDP port numbers, and packet contents. You can also define rules for forwarding, dropping, or accepting packets, among other actions.

Here is an example of how to use the `nftables` command to create a simple firewall rule −

sudo nft add rule ip filter input tcp dport 22 accept

This command will allow incoming TCP traffic on port 22 (SSH), which is useful for remote access to a server.

The `nftables` command uses a hierarchical structure to organize firewall rules, which makes it easier to manage complex configurations. Additionally, `nftables` has a simpler syntax for defining rules, which can help reduce errors and improve security.

6. hostname → hostnamectl

The `hostname` command was used to set or display the hostname of a Linux system. However, it has been deprecated and replaced with the `hostnamectl` command.

`hostnamectl` is a Linux command-line utility used to view and manage the hostname and related system settings on a Linux system. It is available on most modern Linux distributions and is typically used with administrative privileges.

With `hostnamectl`, you can perform a variety of tasks related to the system's hostname and domain name settings, such as −

• View the current hostname and related information

• Set a new static hostname

• Set a new transient hostname (which resets after a reboot)

• Change the system's domain name

Here is an example of how to use the `hostnamectl` command to view the current hostname −

hostnamectl

The output of above command will display the current hostname and other related information.

Conclusion

In this article, we've gone through six deprecated Linux networking commands and their replacements. We've covered the reasons behind the deprecation and how the new commands provide better functionality and features. We've also provided examples of how to use the new commands to make sure your network configurations are consistent and error-free. By adopting these new commands, you can improve your networking experience on Linux and take advantage of the new functionalities provided.