Hello!
For me it was best practice to disable "NetworkManager" on headless installations.
Now suddenly I ran into an problem with several programs not starting correctly upon boot anymore.
The problem seems to be that their unit files contain "After=network.target" but network.target wont wait till network is up and working, just waits for some low level network stuff.
Now I read that it would be good practice to edit this and use "After=network-online.target" instead. But I don't want to touch several systemd unit files shipped via rpm packages.
Software like unbound, postfix and so on which needs to bind to ip+port on startup fails on my systems now since I disabled NetworkManager.
What solved the problem for me was to install "systemd-networkd" instead and enable it upon boot.
It's system unit file pulls in "network.target" as "Wants" this way software that says "After=network.target" will start after network cards are configured. Why there is this behavior I haven't found out yet.
Whats your best practice to archieve stable networking upon reboot? Do you use NetworkManager or systemd-networkd or maybe something exotic anyway?
PS: I have already filed an Bugzilla report here: https://bugzilla.redhat.com/show_bug.cgi?id=1412570
Thanks!