Knowing the speed of your network adapter can be helpful in various scenarios. For instance, it helps you determine whether you can fully utilize the available bandwidth, or if you are planning to upgrade your network, you can check if your current NIC is capable or whether you need to upgrade your NIC.
Regardless of the reason or scenario, there are several command-line tools available to check the NIC speed on a Linux PC.
Find NICs Connected to Your Linux PC
Your system may have single or multiplenetwork interface cardsconnected to it. You can find all the available NICs on Linuxusing the ip command:
It’ll display a list of all the NICs along with their names. Once you find the NIC name, check its speed using either of the methods below.
1. Check Your NIC Speed on Linux Using ethtool
ethtool is a command-line tool that provides information about network drivers and interfaces including their speed, duplexity, network interface statistics, and supported link modes. It also allows you to change network interface configuration settings and you’re able to even use it to troubleshoot your network interface card issues.
You might have ethtool installed on your system. If it’s not, run:
When you run ethtool followed by the NIC name, it displays network interface card details including the speed of the device, duplexity, supported link modes, and some other properties.
To display the speed of a NIC, use:
The output shows that the speed of the NIC is 1000Mb/s.
2. Check the NIC Speed Using the /sys Filesystem
The/sys/class/net/directory contains different files that include information about the network interface cards connected to your system. The speed of NIC is contained in the/sys/class/net//speedfile. you may view this informationusing the cat command:
For instance, to find the speed of the network interfaceens33, the command would be:
The output will display the speed of your NIC.
3. Using dmesg to View the NIC Speed
The dmesg command displays important messages related to system boot and hardware initialization. Using dmesg with the grep command, you can filter out specific information like the speed of a NIC, physical connection state, etc.
To find the speed of your NIC on Linux, run the dmesg command and pipe its output tothe grep commandfollowed by the NIC name:
From the output, you may find your NIC speed among other information such as link state, duplex mode, etc.
4. Use mii-tool to Check Your NIC Speed on Linux
mii-tool is an older Linux command-line tool that allows you to view NIC settings including the link status, duplex mode, and speed of a network interface card. You can use it on older systems where ethtool is not available.
To check the speed of your NIC, run mii-tool followed by NIC name:
5. Using the networkctl Command
networkctl allows you to view and modify the status of network links. Using this command, you can also view information about the links such as type, operation state, speed, model, hardware address, kernel module driver, etc.
To find the speed of your NIC on Linux, use:
This will print the detailed output along with the speed of your NIC. If you only need the NIC speed, pipe the above output to grep as follows:
Finding Your NIC Speed on Linux Is Easy
Knowing the speed of your NIC can help you determine what network speed your card is capable of. Now that you know how to find the NIC speed on your Linux system, you can also speed test your internet connection to check whether you are getting the speed as promised by your ISP.
