When trying to use the WHM > Add IP Address interface, the following error is presented:
The “/sbin/ip -family inet addr add x.x.x.x/y broadcast x.x.x.y dev eno12345678 label eno12345678:cp10” command (process 9999) reported error number 2 when it ended.: RTNETLINK answers: Numerical result out of range
The kernel has a hard limit of 15 characters for the name of an interface. This is intended behavior per RedHat.
If your network interface has a long name, adding additional IPs will try to add 4+ characters to the name of the base interface, starting with ":cp1" and incrementing for each IP.
If the name of your interface + the additional label exceeds 15 characters, the system will be unable to add the interface.
You or your system administrator will need to reduce the length of the interface name. Most long interface names are due to a portion of the MAC address being added to the interface name.
Please see RedHat's documentation on configuring network interfaces.
Additionally, our guide on disabling NetworkManager may be useful to review.
Finally, feel free to consult our System Administration Services.