[Linux] RHEL8网卡命令nmcli

rhel8与7的区别
在rhel7上，同时支持network.service和NetworkManager.service（简称NM）。默认2个服务都开启，但许多人都会将NM禁用掉。

在rhel8上，已废弃network.service，只能通过NM进行网络配置。

[root@xxx ~]# ip addr
1: lo:  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 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host
       valid_lft forever preferred_lft forever
2: em1:  mtu 1500 qdisc mq state UP group default qlen 1000
    link/ether 18:66:da:54:fd:ce brd ff:ff:ff:ff:ff:ff
    inet6 2001:1b70:8822:831:7ad0:6139:720c:7350/64 scope global noprefixroute dynamic
       valid_lft 2591927sec preferred_lft 604727sec
    inet6 fe80::1a34:95c4:bd10:dece/64 scope link noprefixroute
       valid_lft forever preferred_lft forever
3: em2:  mtu 1500 qdisc mq state DOWN group default qlen 1000
    link/ether 18:66:da:54:fd:d0 brd ff:ff:ff:ff:ff:ff
4: em3:  mtu 1500 qdisc mq state UP group default qlen 1000
    link/ether 18:66:da:54:fd:d2 brd ff:ff:ff:ff:ff:ff
5: em4:  mtu 1500 qdisc mq state UP group default qlen 1000
    link/ether 18:66:da:54:fd:d4 brd ff:ff:ff:ff:ff:ff
    inet 10.188.4.84/24 brd 10.188.4.255 scope global em4
       valid_lft forever preferred_lft forever
    inet 40.100.84.1/24 brd 40.100.84.255 scope global secondary em4:1
       valid_lft forever preferred_lft forever
    inet 40.100.84.3/24 brd 40.100.84.255 scope global secondary em4:3
       valid_lft forever preferred_lft forever
    inet 40.100.84.2/24 brd 40.100.84.255 scope global secondary em4:2
       valid_lft forever preferred_lft forever
    inet 10.188.4.218/24 brd 10.188.4.255 scope global secondary em4:218
       valid_lft forever preferred_lft forever
6: virbr0:  mtu 1500 qdisc noqueue state DOWN group default qlen 1000
    link/ether 52:54:00:90:d6:1c brd ff:ff:ff:ff:ff:ff
    inet 192.168.122.1/24 brd 192.168.122.255 scope global virbr0
       valid_lft forever preferred_lft forever
7: virbr0-nic:  mtu 1500 qdisc pfifo_fast master virbr0 state DOWN group default qlen 1000
    link/ether 52:54:00:90:d6:1c brd ff:ff:ff:ff:ff:ff
[root@xxx ~]#

说明：virbr0网卡有一个固定的默认IP 地址192.168.122.1，和virbr0-nic都是因为安装系统的时候附带了libvirt服务生成的

nmcli connection 连接，可理解为配置文件，相当于ifcfg-ethX，可以简写为 nmcli c

nmcli device 设备，可理解为实际存在的网卡（包括物理网卡和虚拟网卡），可以简写为 nmcli d

重载网络配置
nmcli c reload

启动网络接口
nmcli c up ens33

查看网卡信息
nmcli connection
nmcli c

[root@xxx ~]# nmcli c
NAME    UUID                                  TYPE      DEVICE
em1     182531a5-6514-42d8-96ad-f916906d24e1  ethernet  em1
em4     302f339a-2ac4-45db-8e6b-78fe3e73e0e2  ethernet  em4
virbr0  1986eabe-259e-430a-b8cf-f5c4f6830d87  bridge    virbr0
[root@xxx ~]#

查看设备信息
nmcli device
nmcli d

[root@xxx ~]# nmcli d
DEVICE      TYPE      STATE         CONNECTION
em1         ethernet  connected     em1
em4         ethernet  connected     em4
virbr0      bridge    connected     virbr0
em2         ethernet  disconnected  --
em3         ethernet  disconnected  --
lo          loopback  unmanaged     --
virbr0-nic  tun       unmanaged     --
[root@xxx ~]#

显示具体的网络接口信息
nmcli connection show ens33
nmcli c show ens33
 

参考资料：
RHEL8怎么重启网络服务 https://blog.csdn.net/qq_45617652/article/details/102690087
RHEL8/CentOS8的网络网卡配置&常用命令详解 https://www.cnblogs.com/fengdejiyixx/p/14631805.html