Note coreos-installer --copy-network

as noted in review by steve hardy

enhancements/host-network-configuration.md

@@ -144,7 +144,8 @@ behavior, an admin can:
   additions can configure additional networking
 * If using the RHCOS live ISO/PXE ramdisk environment with the
   coreos-installer, use the `nmtui` Network Manager text UI to configure
-  networking before proceeding
+  networking before proceeding.  Those settings can be automatically propogated
+  to the installed host, as well.
 
 #### Further Network Customization
 
@@ -329,6 +330,13 @@ networking](https://github.com/openshift/enhancements/pull/291) in the ramdisk:
 networking configuration via Ignition if the administrator does not want to
 follow an interactive configuration process.
 
+The `coreos-installer` also includes a
+[`--copy-network`](https://github.com/coreos/coreos-installer/pull/212) option
+which can be used to persist whatever network configuration was done using
+`nmtui` to the resulting installed host.  There is a [dracut
+module](https://github.com/coreos/fedora-coreos-config/pull/346) which will
+apply these settings in the initramfs.
+
 These enhancements provide some excellent improvements to early network
 configuration capabilities.  However, it is currently most beneficial to the
 UPI bare metal flow.  The IPI bare metal flow will need to do more work to