[Administrative] [CentOS] [NetworkManager] NetworkManager (ii)

Engineering Documents:

Https://wiki.gnome.org/Projects/NetworkManager

RH Admin Manual:

https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/html/Networking_Guide/

NMCLI User manual:

Https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/7/html/networking_guide/sec-network_ Config_using_nmcli

After basic understanding, see help directly. The main is to understand Connect,device, and so on these concepts.

[Email protected] j]# NMCLI Help

Next, do an example to try:

Add a tap device:

[[email protected] j]# nmcli connection NAME UUID TYPE DEVICE ens33 E46 72331-0638-4db8-b818-d6ff50f901af802-3-Ethernet ENS33 [[email protected] jcloud]# nmcli Connection Add type Tun mode TAP ifname tap-NLB Con-name tap-NLB AutoConnect Yes save yesconnection'TAP-NLB'(b3e1db65-4821-4139-95f5-9cba4035ee08) successfully added. [[email protected] j]# nmcli connection NAME UUID TYPE DEVICE ens33 e4 672331-0638-4db8-b818-d6ff50f901af802-3-Ethernet ENS33 Tap-NLB b3e1db65-4821-4139-95f5-9cba4035ee08 Tun tap-NLB [[email protected] j]#

The generated configuration file is here:

[Email protected] j]# cat/etc/networkmanager/system-connections/tap-NLB [connection]id=tap-nlbuuid =b3e1db65-4821-4139-95f5-9cba4035ee08type=tuninterface-name= tap-nlbpermissions=[Tun]mode=2[Ipv4]dns-search=Method=  Auto[ipv6]addr-gen-mode=stable-privacydns-search=method=auto

To modify the DHCP that disables tap:

[Email protected] ~]# NMCLI connection Modify TAP-NLB Ipv4.method link-local

To remove a tap connection device:

[[email protected] ~]# NMCLI Connection Delete tap-'tap-nlb' (b3e1db65-4821 -4139-95f5-9cba4035ee08) successfully deleted.

The device is automatically added or removed when connected to Up/down and can be viewed with NMCLI device.

Another example is to add a bridge to the external network:

1. To add a network bridge:

[[Email protected]~]# nmcli Connection Add type BRIDGE ifname br-ext AutoConnect Yes save Yes Connection'Bridge-br-ext'(e886ae77-3a2c-4c93-aee0-4dea8b4d12a8) successfully added. [[Email protected]~]# nmcli Connection showname UUID TYPE DEVICE Bridge-br-ext E886ae77-3a2c-4c93-aee0-4dea8b4d12a8 Bridge br-ext ens33 e4672331-0638-4db8-b818-d6ff50f901af802-3-Ethernet ENS33 [[email protected]~]# nmcli devicedevice TYPE State CONNECTION Ens33 Ethernet connected Ens33 BR-ext Bridge connecting (getting IP configuration) bridge-br-ext lo Loopback unmanaged--

2. Increase slave

[Email protected] ~]# nmcli connection Add type Bridge-slave ifname ens33 master Br-ext

3. Switch the connection from the NIC to bridge

[[email protected] jcloud]# NMCLI connection down Ens33[[email protected] jcloud]# nmcli connection up bridge-sla Ve-ens33

4. Erase the principle of connect

5. Reboot test

6 successes. NetworkManager learned to use it.

[[Email protected] ~]# IP Link1: Lo: <LOOPBACK,UP,LOWER_UP> MTU65536Qdisc Noqueue State UNKNOWN mode DEFAULT Qlen1Link/loopbackxx:xx:xx:xx:xx:xxBrdxx:xx:xx:xx:xx:xx2: Ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> MTU theQdisc Pfifo_fast Master Br-ext State up mode DEFAULT Qlen +Link/etherxx: 0c: in: 2F:CF: +BRD FF:FF:FF:FF:FF:FF3:Br-ext:<BROADCAST,MULTICAST,UP,LOWER_UP> MTU theQdisc Noqueue State up mode DEFAULT Qlen +Link/etherxx: 0c: in: 2F:CF: +BRD Ff:ff:ff:ff:ff:ff[[email protected]~]# IP Addr1: Lo: <LOOPBACK,UP,LOWER_UP> MTU65536Qdisc Noqueue State UNKNOWN Qlen1Link/loopbackxx:xx:xx:xx:xx:xxBrdxx:xx:xx:xx:xx:xxinet127.0.0.1/8Scope host lo valid_lft forever Preferred_lft Forever Inet6::1/ -Scope host Valid_lft forever Preferred_lft forever2: Ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> MTU theQdisc Pfifo_fast Master Br-ext State up Qlen +Link/etherxx: 0c: in: 2F:CF: +BRD FF:FF:FF:FF:FF:FF3: Br-ext: <BROADCAST,MULTICAST,UP,LOWER_UP> MTU theQdisc Noqueue State up Qlen +Link/etherxx: 0c: in: 2F:CF: +BRD ff:ff:ff:ff:ff:ff inet192.168.50.128/24Brd192.168.50.255ScopeGlobal Dynamicbr-ext valid_lft 1771sec preferred_lft 1771sec inet6 fe80::1ecf:c3cc:4ff6:ef29/ -scope link Valid_lft forever preferred_lft forever[[email protected]~]# brctl Showbridge name Bridge ID STP enabled INTERFACESBR-ext8000.000C292FCF32 YesEns33

Other than that:

The NMCLI tap device is invisible in the Nmtui. and cannot be edited. So the preferred or nmcli.

[Administrative] [CentOS] [NetworkManager] NetworkManager (ii)