TCP/IP Commands for Linux: A Complete List

IP networking is at the center of how today’s smart devices communicate with each other over networks, including the internet. 

IP stands for “Internet Protocol,” and it is part of the TCP/IP protocol suite that defines common standards for computer networks to exchange data.

In particular, IP governs how unique addresses are assigned to each device and how data packets are routed between sources and destinations. Linux and other operating systems include IP commands, which are specialized tools that configure and manage the TCP/IP network stack. 

Learning core IP commands allows Linux administrators to control IP addressing, network connectivity, routing policies, firewall access, and more. 

What are IP Commands?

IP commands provide access to networking parameters and allow administrative control over how TCP/IP is implemented in an operating system. In Linux, common commands include ip, ipconfig, and route, but there are many other useful commands. (We’ll get to a list of them in just a bit!)

Network engineers and IT professionals rely on these tools to set up and manage network services. IP commands enable critical functions, including:  

• Assigning IP addresses
• Bringing network interfaces up or down
• Defining routes between networks
• Configuring firewall policies 

Without IP commands, operating systems would not have the ability to connect to networks, connect to the internet, or provide customization needed for different environments.

Why are TCP/IP Commands Important for Linux Users?

There are several reasons why TCP/IP commands are important for Linux users. 

• Netflix configuration and management
• Troubleshooting and diagnostics
• Security enhancement
• Customization and optimization
• Server and service configuration
• Learning and skill development
• Cross-platform compatibility 

Let’s take a look at some of the things that TCP/IP commands can do. Then we’ll provide you with the Linux commands for many of these tasks. 

Working with Network Interfaces

A key concept in IP networking is the idea of network interfaces. These virtual connections represent physical hardware ports that allow a device to communicate with one or more networks. 

For example, a server may have physical Ethernet interfaces called eth0, eth1, etc. A virtual machine, on the other hand, would have a tun or tap interface. IP commands are used to configure the parameters on these interfaces and determine how they connect to a network. 

TCP/IP commands can be issued that allow the programmer to:

• View status information like MAC address, speed, IP addresses
• Enable/disable interfaces or set to modes like promiscuous
• Assign IP addresses and subnet masks to interfaces
• Define gateway and DNS settings used by interfaces
• Bring interfaces up or down as needed

This interface configuration directs how data will be sent and received on a given network link. Routes must then channel traffic between interfaces to reach other networks and devices. 

Controlling IP Addresses

IP addresses serve as unique identifiers for devices on a TCP/IP network. Data packets are routed between sources and destinations based on these IP addresses. Linux and Windows systems alike use IP commands to manage address assignments. 

Some common tasks that TCP/IP commands allow: 

• Add or remove static IP addresses from interfaces
• Define primary and secondary IP addresses on an interface
• Display currently assigned addresses and interface properties
• Leverage DHCP for dynamic address allocation
• Manage Address Resolution Protocol (ARP) mappings

Proper IP configuration ensures efficient routing by establishing accessible addresses optimized for the network architecture. 

Managing Routes and Traffic Flow

Network routing directs the traffic path between networks and devices. 

IP commands allow administrators to define routing policies and tables that decide how packets should be forwarded based on destination IP. This includes:

• Setting the default gateway used for external traffic
• Adding or removing static routes for specific IP
•  ranges
• Listing and modifying dynamic routes learned through routing protocols
• Changing route metrics and priorities to influence traffic
• Optimizing performance by adapting routes based on network conditions

Careful routing configuration provides better throughput while also enhancing security.

Firewalls and Access Control

Firewall policies filter traffic and connections based on sets of IP rules. 

Linux systems employ iptables commands to define firewall settings. This may include:

• Adding and removing rules to accept or reject certain packets
• Allowing or blocking traffic based on IP addresses, protocols, ports
• Using rules to limit access and implement access control
• Leveraging firewall capabilities provided by IP commands

IP-based firewall policies enable safe public connectivity by restricting inappropriate or malicious traffic.

How Many Linux TCP/IP Commands Are There?

There is no definitive single number of TCP/IP commands available in Linux. The core TCP/IP commands number around 15-20, but there are many additional utilities that relate to TCP/IP networking in some capacity.

Some key points:

• The core commands for IP address management, routing, DNS, firewalls, etc. are in the 15-20 range. These include ip, ifconfig, route, iptables, ping, traceroute etc.
• There are dozens of additional utilities that connect to TCP/IP functionality like netstat, ss, dig, nmap, tcpdump. The exact count depends on the distribution.
• Commands for network troubleshooting and monitoring can relate to TCP/IP, like ping, traceroute, netstat, lsof, wireshark and many more.
• Wireless network configs add commands like iwconfig, iwlist, iwspy.
• Kubernetes networking includes commands like kubectl that interact with TCP/IP.
• Commands for network configuration management like Ansible, Chef, and Puppet utilize TCP/IP extensively.

So while the core IP command count is reasonably small, there are very likely over 100 commands that relate to TCP/IP services in a typical Linux distribution once you include networking utilities, wireless tools, virtualization, configuration management, etc. However, a typical admin would only regularly use a subset of these day-to-day.

A List of Common Linux TCP/IP Commands

Here is a list of some of the most commonly used TCP/IP commands in Linux systems: 

• ip: The main command for configuring IP network interfaces, routing, and more in modern distros. Replaces ifconfig.
• ifconfig: Older command for configuring IP network interfaces. Still included but deprecated.
• ip addr: Configure IP addresses assigned to interfaces, including adding/removing addresses.
• ip route: View and modify IP routing tables, add static routes, set default gateways.
• ip rule: Manage IP routing policies and rules.
• ip neigh: View and edit ARP cache and neighbor tables for IP to MAC resolution.
• ping: Test IP connectivity to another host.
• traceroute: Trace the route IP packets take to a remote host.
• tracepath: Similar to traceroute but with additional IP packet information.
• netstat: Display IP network connections, routing tables, interface stats.
• ss: Inspect active IP sockets and connections. Replaces netstat in some distros.
• dig: Query DNS servers for IP address lookup information.
• iptables: Configure IP firewall rules to filter traffic and connections.
• route: Legacy command similar to ip route for viewing and modifying IP routing tables.

Linux and other operating systems include specialized IP commands to configure and manage TCP/IP services. These tools allow fine-grained control over IP addressing, network interfaces, routing, firewall policies, and more. 

IP commands establish core networking capabilities that enable devices to securely communicate and participate in modern networks and the internet. Whether optimizing performance or restricting access, mastering IP commands is essential for effective network administration in Linux. Additionally, Unix TCP/IP commands and IP commands for DOS/Windows are crucial for managing and troubleshooting network issues across different operating systems. Understanding these commands ensures secure and efficient communication within various network environments, aiding in robust network management and problem resolution.

Frequently Asked Questions

How to use TCP/IP command?

Commands used to display TCP/IP and network information include NETSTAT, PING, and TRACERTE. The following commands can be issued from an ISPF/TSO session. By omitting the TSO prefix, the same commands can be entered at a UNIX System Services prompt. However, the command must be in lower case.

What are the Linux commands for IP addresses?

The following commands will get you the private IP address of your interfaces:

• ifconfig -a
• ip addr (or ip a)
• hostname -I | awk '{print $1}'
• ip route get 1.2.3.4 | awk '{print $7}'

Fedora: Wifi-Settings → Click the settings icon next to the Wifi name you are connected to → IPv4 and IPv6 both can be seen.