Upgraded some boxes to Fedora 29 and after a while I came across this bit of fun: the old network-scripts ifcfg style of configuring your network interfaces is deprecated and will be removed from Fedora eventually. I checked and Ubuntu seems to have done the same (actually, they are moving faster). This means RHEL/CentOS will have this in the near future also.
The new "solution" is to use NetworkManager (of course). Strike another win for the "systemd crowd", and another loss for any advanced admin running servers with moderately complex, mostly static, network setups.
So we'll all have to convert our ifcfg setups to NM format, which of course won't have a 1-for-1 replacement for every option. And we'll have to then figure out how to fight NM not to do anything automatically. And we'll (for many people, but not all) be forced to have NMd running in the background always and forever, even on static setups.
Oh joy.
Here's some bz ranting (no, the guy isn't me, but could be!) https://bugzilla.redhat.com/show_bug.cgi?id=1643763
At least it looks like it'll be in deprecated mode in Fedora for a few versions so one is not forced to change immediately. Ubuntu users may not be so lucky. As for now, my box had the networks come up just fine as usual when I upgraded, and I don't even have the NM rpms installed at all. But the migration will have to come sooner rather than later...
ifup enp5s0.4 WARN : [ifup] You are using 'ifup' script provided by 'network-scripts', which are now deprecated. WARN : [ifup] 'network-scripts' will be removed from distribution in near future. WARN : [ifup] It is advised to switch to 'NetworkManager' instead - it provides 'ifup/ifdown' scripts as well.