This error is presented when attempting to bring up a network connection using nmcli. The connection name can be anything, of course.
There is a RedHat bug on this titled "RHEL 7 syslog shows failure related to network.service" bug #1079353.
There is no fix listed in the bug. I've seen this on a virtual machine, and the easiest work around was to delete the virtual machine's NIC, reboot, add a new NIC - reboot. After doing that, I deleted the new network connection using nmcli and applied the new device to the original connection profile I was attempting to use.