Network interface is not available after installing CloudLinux

Issue

A network interface cannot be enabled after installing CloudLinux:

Environment

• CloudLinux 7/7h/8
• The latest motherboards models with RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (in most cases provided by Hetzner)

Solution

1. Check Ethernet controller model:
   

   # lspci |grep -i ether
   
   03:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 15)

2. Check motherboard model:
   

   # dmidecode -t 2
   1. dmidecode 3.2
   Getting SMBIOS data from sysfs.
   SMBIOS 2.8 present.Handle 0x0002, DMI type 2, 15 bytes
   Base Board Information
          Manufacturer: ASUSTeK COMPUTER INC.
          Product Name: PRIME B360M-A
   

3. If the Ethernet controller and motherboard model matched - this hardware is not supported.
   CloudLinux supports all the hardware that RHEL supported. 
   You can find all supported devices following this link:
   catalog.redhat.com/hardware/components/search?p=1&c_version=Red%20Hat%20Enterprise%20Linux%208 
   

Cause

RHEL removed support for some networking cards in RHEL8 on which our kernel 4.x branch is based on, and this includes the networking chipset on the latest main boards for gamers.