Here we'll resolve the common Fedora / RHEL 7 network startup issue: Failed to start LSB: Bring up/down networking

This error is accompanied by a number of subissues:

• Device eth0 has different MAC address than expected, ignoring.
• RTNETLINK answers: File exists

For the first issue, ensure that your definition in the ifcfg-eth0 file really matches the ifconfig output:

# cat /etc/sysconfig/network-scripts/ifcfg-eth0
DEVICE=eth0
IPV6INIT=no
BOOTPROTO=none
NM_CONTROLLED=no
ONBOOT=yes
NETMASK=255.255.255.0
IPADDR=192.168.0.36
GATEWAY=192.168.0.1
HWADDR=00:0D:88:38:0A:34
DNS=192.168.0.1

as compared with:

# ifconfig eth0
eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 192.168.0.36  netmask 255.255.255.0  broadcast 192.168.0.255
        inet6 fe80::20d:88ff:fe38:a34  prefixlen 64  scopeid 0x20<link>
        ether 00:0d:88:38:0a:34  txqueuelen 1000  (Ethernet)
        RX packets 7438  bytes 8067940 (7.6 MiB)
        RX errors 0  dropped 32  overruns 0  frame 0
        TX packets 4905  bytes 569984 (556.6 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

For the second issue, ensure you remove any previous definitions of ifcfg-eth0 even if renamed and given prefixes.  The Linux Networking script will pick this up:

# rm -f back.ifcfg-eth0 back.ifcfg-eth1 old.ifcfg-eth1 old.ifcfg-eth2 strace-ifup.txt lshal-list.txt dhcp.ifcfg-wlan0 static.ifcfg-wlan0 2ISNOW0.ifcfg-eth2 FRIED.ifcfg-eth0 Dec.19.2011.ifcfg-eth2

And that should get you going.

Also don't forget to change your UDEV rules:

[root@mysql02 rules.d]# cat 90-eno-fix.rules
# This file was automatically generated on systemd update
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:50:56:86:b5:1b", NAME="eno16782080"
[root@mysql02 rules.d]#

to:

[root@mysql02 rules.d]# cat 90-eno-fix.rules
# This file was automatically generated on systemd update
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:50:56:86:b5:1b", NAME="eth0"
[root@mysql02 rules.d]#

Good Luck!

Cheers,
TK