Detailed explanation of nmcli usage in CentOS8

# View IP (similar to ifconfig, ip addr)
nmcli
# Create a connection, configure a static IP (equivalent to configuring ifcfg, where BOOTPROTO=none, and start it with ifup)
nmcli c add type ethernet con-name ethX ifname ethX ipv4.addr 192.168.1.100/24 ​​ipv4.gateway 192.168.1.1 ipv4.method manual
# Create a connection and configure a dynamic IP (equivalent to configuring ifcfg, where BOOTPROTO=dhcp and ifup is used to start the connection)
nmcli c add type ethernet con-name ethX ifname ethX ipv4.method auto
# Modify ip (non-interactive)
nmcli c modify ethX ipv4.addr '192.168.1.200/24'
nmcli c up ethX
# Modify ip (interactive)
nmcli c edit ethX
nmcli> goto ipv4.addresses
nmcli ipv4.addresses> change
Edit 'addresses' value: 192.168.1.200/24
Do you also want to set 'ipv4.method' to 'manual'? [yes]: yes
nmcli ipv4> save
nmcli ipv4> activate
nmcli ipv4> quit
# Enable connection (equivalent to ifup)
nmcli c up ethX
# Stop connection (equivalent to ifdown)
nmcli c down
# Delete connection (similar to ifdown and delete ifcfg)
nmcli c delete ethX
# View the connection list nmcli c show
# View connection details nmcli c show ethX
# Reload all ifcfg or route to connection (will not take effect immediately)
nmcli c reload
# Reload the specified ifcfg or route to connection (will not take effect immediately)
nmcli c load /etc/sysconfig/network-scripts/ifcfg-ethX
nmcli c load /etc/sysconfig/network-scripts/route-ethX
# Connection takes effect immediately. There are three methods: nmcli c up ethX
nmcli d reapply ethX
nmcli d connect ethX
# View the device list nmcli d
# View all device detailed information nmcli d show
# View detailed information about the specified device nmcli d show ethX
# Activate the network card nmcli d connect ethX
# Disable wireless network (NM enables wireless network by default)
nmcli r all off
# Check the NM management status nmcli n
# Enable NM management nmcli n on
# Disable NM management (execute with caution)
nmcli n off
#Monitoring events nmcli m
# View the status of NM itself nmcli
# Check whether NM is available online nm-online