[CentOS] CentOS 7.5 (1804) and NetworkManager

Tue May 15 11:19:34 UTC 2018
Gianluca Cecchi <gianluca.cecchi at gmail.com>

On Tue, May 15, 2018 at 12:40 PM, Nicolas Kovacs <info at microlinux.fr> wrote:

> Hi,
> I'm running CentOS on all kinds of setups: servers, workstations,
> desktops and laptops.
> Up until now, I'm only using NetworkManager on laptops, since it makes
> sense to use it there. On servers and desktop clients, I usually remove
> it and configure the network "traditionally" by simply editing
> /etc/sysconfig/network-scripts/ifcfg-whatever, /etc/resolv.conf,
> /etc/hosts, /etc/hostname and /etc/sysconfig/network. Running
> NetworkManager on anything else than a laptop has never made any sense
> to me, since it's basically an extra layer of abstraction.
> With the latest update, the removal of NetworkManager on a desktop
> client isn't possible anymore, since 'yum remove NetworkManager' also
> tries to remove 'gdm', and disabling it on startup spews back all sorts
> of errors.
> If you folks at Red Hat are reading this, I have one question: WHY ?
> Niki Kovacs

I'm not a folk at Red Hat ;-)

In CentOS / Fedora I simply disable NetworkManager service and put into
ifcfg-xxx (eg ifcfg-eth0) the line


The network service is enabled by default, so this should be sufficient to
keep NetworkManager installed but not inerfering with your classic network

On a just updated c7test vm

[root at c7test ~]# uptime
 13:19:51 up 2 min,  1 user,  load average: 0.10, 0.15, 0.07
[root at c7test ~]#

[root at c7test ~]# cat /etc/centos-release
CentOS Linux release 7.5.1804 (Core)
[root at c7test ~]#

[root at c7test ~]# systemctl status NetworkManager
● NetworkManager.service - Network Manager
   Loaded: loaded (/usr/lib/systemd/system/NetworkManager.service;
disabled; vendor preset: enabled)
   Active: inactive (dead)
     Docs: man:NetworkManager(8)

[root at c7test ~]# systemctl status network -l
● network.service - LSB: Bring up/down networking
   Loaded: loaded (/etc/rc.d/init.d/network; bad; vendor preset: disabled)
   Active: active (exited) since Tue 2018-05-15 13:17:27 CEST; 15s ago
     Docs: man:systemd-sysv-generator(8)
  Process: 700 ExecStart=/etc/rc.d/init.d/network start (code=exited,

May 15 13:17:21 c7test.mydomain systemd[1]: Starting LSB: Bring up/down
May 15 13:17:23 c7test.mydomain network[700]: Bringing up loopback
interface:  [  OK  ]
May 15 13:17:27 c7test.mydomain NET[1001]:
/etc/sysconfig/network-scripts/ifup-post : updated /etc/resolv.conf
May 15 13:17:27 c7test.mydomain network[700]: Bringing up interface eth0:
[  OK  ]
May 15 13:17:27 c7test.mydomain systemd[1]: Started LSB: Bring up/down

[root at c7test ~]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group
default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host
       valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state
UP group default qlen 1000
    link/ether 00:1a:4a:16:01:00 brd ff:ff:ff:ff:ff:ff
    inet brd scope global eth0
       valid_lft forever preferred_lft forever
    inet6 fe80::21a:4aff:fe16:100/64 scope link
       valid_lft forever preferred_lft forever
[root at c7test ~]#