5.21 NetworkManager fails to set the default gateway and route for interfaces configured with DHCP on UEK R3

When running UEK R3 on Oracle Linux 7 Update 4 and later, NetworkManager fails to set the default gateway and route for network interfaces that are configured with DHCP. This can result in network interfaces not behaving correctly.

The workaround for this issue is to disable NetworkManager control over interfaces that are configured for DHCP.

To disable NetworkManager for an interface, edit the network script for the interface in /etc/sysconfig/network-scripts/ifcfg-dev and add the parameter NM_CONTROLLED=no, as shown in the following example:

# echo "NM_CONTROLLED=no" >> /etc/sysconfig/network-scripts/ifcfg-eno4

(Bug ID 26268996)