Created attachment 759604 [details]
journal wit log-priority=debug

Netinstall, 3 network devices, only one (em1) has link.

From journal:

initramfs

Jun 10 12:24:31 localhost systemd-udevd[315]: renamed netif to 'em1'
Jun 10 12:24:31 localhost systemd-udevd[315]: renamed network interface eth0 to em1
Jun 10 12:24:31 localhost systemd-udevd[310]: renamed netif to 'p3p1'
Jun 10 12:24:31 localhost systemd-udevd[310]: renamed network interface eth0 to p3p1
Jun 10 12:24:43 localhost systemd-udevd[373]: renamed network interface eth1 to p3p2
Jun 10 12:24:43 localhost systemd-udevd[373]: renamed netif to 'p3p2'

switchroot

Jun 10 12:24:59 gasoline.anaconda.englab.brq.redhat.com englab.brq.redhat.com br systemd-udevd[738]: '/lib/udev/rename_device' [754] exit with return code 0
Jun 10 12:24:59 gasoline.anaconda.englab.brq.redhat.com englab.brq.redhat.com br systemd-udevd[739]: '/lib/udev/rename_device'(out) 'em1'
Jun 10 12:24:59 gasoline.anaconda.englab.brq.redhat.com englab.brq.redhat.com br systemd-udevd[739]: '/lib/udev/rename_device' [758] exit with return code 0
Jun 10 12:24:59 gasoline.anaconda.englab.brq.redhat.com englab.brq.redhat.com br systemd-udevd[736]: '/lib/udev/rename_device' [753] exit with return code 0
Jun 10 12:24:59 gasoline.anaconda.englab.brq.redhat.com englab.brq.redhat.com br systemd-udevd[738]: renamed network interface p3p2 to ens3f1
Jun 10 12:24:59 gasoline.anaconda.englab.brq.redhat.com englab.brq.redhat.com br systemd-udevd[736]: renamed network interface p3p1 to ens3f0

One of the devices - em1/enp63s0 is activated in initramfs and therefore ifcfg file (ifcfg-em1 containing DEVICE=em1) is created.

ifcfg-em1:
# Generated by dracut initrd
DEVICE="em1"
ONBOOT=yes
NETBOOT=yes
UUID="c032d129-1904-4df0-8bfe-10d3b1c1b543"
BOOTPROTO=dhcp
HWADDR="f4:ce:46:2c:44:7a"
TYPE=Ethernet
NAME="em1"


For the two remaining - p3p1/ens3f0, p3p2/ens3f1 - ifcfg files (ifcfg-ens3fX, with NO DEVICE= line) are created after switch root in anaconda (the devices are not named by biosdevname)

ifcfg-ens3f1:
TYPE=Ethernet
BOOTPROTO=dhcp
DEFROUTE=yes
IPV4_FAILURE_FATAL=no
IPV6INIT=yes
IPV6_AUTOCONF=yes
IPV6_DEFROUTE=yes
IPV6_PEERDNS=yes
IPV6_PEERROUTES=yes
IPV6_FAILURE_FATAL=no
NAME=ens3f0
UUID=47b9e38e-726c-45fe-b0b9-d30bad0af4d4
ONBOOT=no
HWADDR=00:15:17:96:75:0A
PEERDNS=yes
PEERROUTES=yes

(I will attach journalctl and output of udevadm test for network devices.)

So after switchroot, in anaconda, devcices are named em1, ens3f1, ens3f0.
After reboot, the devices would be renamed using biosdevname (em1, p3p1, p3p2).
Seems that for the em1 case only initscript's 60-net.rules (renaming device to DEVICE from ifcfg) prevents changing device name to enp63c0 later (by 80-net-name-slot.rules), which is not the case for the other two devices. Without creating ifcfg-em1 in initramfs em1 would be ranamed too during installation after switchroot:

Jun 10 13:05:21 localhost systemd-udevd[322]: renamed netif to 'em1'
Jun 10 13:05:21 localhost systemd-udevd[322]: renamed network interface eth0 to em1
Jun 10 13:05:21 localhost systemd-udevd[322]: renamed netif to 'p3p1'
Jun 10 13:05:21 localhost systemd-udevd[322]: renamed network interface eth0 to p3p1
Jun 10 13:05:34 localhost systemd-udevd[378]: renamed netif to 'p3p2'
Jun 10 13:05:34 localhost systemd-udevd[378]: renamed network interface eth1 to p3p2

Jun 10 13:06:03 localhost systemd-udevd[661]: PROGRAM '/lib/udev/rename_device' /usr/lib/udev/rules.d/60-net.rules:1
Jun 10 13:06:05 localhost systemd-udevd[673]: renamed network interface em1 to enp63s0
Jun 10 13:06:07 localhost systemd-udevd[661]: renamed network interface p3p2 to ens3f1
Jun 10 13:06:07 localhost systemd-udevd[680]: renamed network interface p3p1 to ens3f0

So if we don't take into account 60-net.rules (ie when ifcfg file with DEVICE=em1 is not created in intramfs), it seems that after switchroot 80-net-name-slot.rules is triggered and it renames devices to en* which would (?) be prevented if the devices had been named by 71-biosdevname (NAME!="", GOTO="net_name_slot_end")?