Each Dedicated Server has multiple network cards connected to separate network switches, but the installed OS activates only the 1 Gbps card by default. A 10 Gbps network card must already be installed on the server — Gcore can add one as part of a server upgrade.
These steps require direct server access and manual network configuration. Consult a system administrator if difficulties arise.
Ubuntu and Debian use netplan for network configuration. On older systems without netplan, each step includes the equivalent command.Install the required tools
Install ethtool, net-tools, and nano, or another text editor of choice. Check active interfaces
Run ip to list active network interfaces.The output resembles the following, where eth0 is the active 1 Gbps interface.On older Linux versions where ip is not available, use ifconfig instead. Check interface settings
Inspect the settings of the active interface to confirm its speed.The output resembles the following:In Supported link modes, 1000baseT/Full means the interface supports a maximum speed of 1 Gbps. Find an interface that lists 10000baseT/Full, which indicates 10 Gbps support. List all interfaces
List all interfaces, including inactive ones, to find the 10 Gbps candidate.The output lists each interface and its state (up or down).On older Linux versions where ip link show is not available, use ifconfig instead. Activate inactive interfaces
Bring up each interface that is listed as down. Replace eth1 and eth2 with the interface names shown in the previous step.On older Linux versions, use ifconfig eth1 up instead of ip link set. To verify that an interface is active, run ip and check for state UP in the output (state DOWN means the interface is still inactive; use ifconfig on older systems). Find the 10 Gbps interface
Run ethtool on each inactive interface until finding the one that supports 10 Gbps.The output resembles the following:Confirm that Link detected is yes and Speed is 10000Mb/s (10 Gbps). Note the interface name — the next step requires it. Update the network configuration
Open the network configuration file in a text editor.On older Linux versions, use nano /etc/network/interfaces instead.In the configuration file, find every line where the current 1 Gbps interface name (eth0) appears and replace it with the 10 Gbps interface name identified in the previous step. Leave the lo interface unchanged.If the 10 Gbps interface is eth2, a section that reads:becomes: Apply the configuration
Save the file and exit the text editor, then apply the new configuration.On older Linux versions that do not use netplan, reboot the server instead.If the server becomes unreachable after applying, reboot it to recover. If it still does not respond, use IPMI to access it. Verify the active interface
Run ethtool on the 10 Gbps interface name to confirm Speed shows 10000Mb/s. The server now uses the 10 Gbps network interface.If the interface is not active, reboot the server and check again. If the server does not respond, use IPMI to access it, or reinstall the OS. CentOS 7 reached end of life on June 30, 2024. For new servers, consider using AlmaLinux or Rocky Linux as actively maintained alternatives. The steps below apply to CentOS 7.
/etc/sysconfig/network-scripts/ for network configuration. On older systems without the ip utility, each step includes the equivalent command.Install the required tools
Install ethtool, net-tools, and nano, or another text editor of choice. Check active interfaces
Run ip to list active network interfaces.The output resembles the following, where eno1 is the active 1 Gbps interface.On older Linux versions where ip is not available, use ifconfig instead. Check interface settings
Inspect the settings of the active interface to confirm its speed.The output resembles the following:In Supported link modes, 1000baseT/Full means the interface supports a maximum speed of 1 Gbps. Find an interface that lists 10000baseT/Full, which indicates 10 Gbps support. List all interfaces
List all interfaces, including inactive ones, to find the 10 Gbps candidate.The output lists each interface and its state (up or down).On older Linux versions where ip link show is not available, use ifconfig instead. Activate inactive interfaces
Bring up the interface that is listed as down. Replace eno2 with the interface name shown in the previous step.On older Linux versions, use ifconfig eno2 up instead of ip link set. To verify that the interface is active, run ip and check for state UP in the output (state DOWN means the interface is still inactive; use ifconfig on older systems). Find the 10 Gbps interface
Run ethtool on each inactive interface until finding the one that supports 10 Gbps.The output resembles the following:Confirm that Link detected is yes and Speed is 10000Mb/s (10 Gbps). Note the interface name — the next step requires it. Update the network configuration
Open the configuration file for the current 1 Gbps interface and disable it by setting ONBOOT=no.Then open the configuration file for the 10 Gbps interface. Replace eno1 in the filename with the 10 Gbps interface name identified in the previous step.In ifcfg-eno2, copy the IP address, subnet mask, gateway, and DNS settings from ifcfg-eno1, then update DEVICE and NAME to the 10 Gbps interface name and set ONBOOT=yes. Save and reboot
Save the file and exit the text editor. Reboot the server for the changes to take effect.
Verify the active interface
After the reboot, run ethtool on the 10 Gbps interface name to confirm Speed shows 10000Mb/s. The server now uses the 10 Gbps network interface.If the server does not respond after reboot, use IPMI to access it, or reinstall the OS. 
