Network

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Network Settings

apt-get install network-manager

$ sudo systemctl start NetworkManager.service 

$ sudo systemctl enable NetworkManager.service 

$ nmtui 

apt install net-tools 

# apt-get install ifupdown

# ifdown enp0s3; ifup enp0s3

apt-get install ifupdown

apt-get install ifupdown2

apt-get install netscript-2.4

# ip link set dev eth0 up

# ip link set dev eth0 down

# /sbin/ifconfig eth0 up

# /sbin/ifconfig eth0 down

# sudo ip addr add 10.102.66.200/24 dev enp2s0

# ip link set dev enp2s0 up

# ip link set dev enp2s0 down

# sudo ip route add default via 10.102.66.1

# ip route show

# ifconfig -a

# netplan generate 

apt install net-tools 

$ ip a 

$ ifconfig enp0s3 up
$ ifconfig enp0s3 down 

**** 2 network interfaces *******

LAN: enp0s3 WAN: enp0s8 

# cd /etc/netplan

$ sudo nano /etc/netplan/50-cloud-init.yaml    [ Ubuntu 18.04]

# vim /etc/netplan/01-netcfg.yaml

---------------------------------------------

#  vi  /etc/netplan/01-systemd-networkd.yaml

#   netplan apply 

# network: {config: disabled}

               ---------------

### 1 LAN card 

enp0s8: 

dhcp4: no

dhcp6: no

addresses: [192.168.56.110/24, ]

gateway4: 192.168.56.1

nameservers:

addresses: [8.8.8.8, 8.8.4.4]

#### 2 LAN Card

# This file describes the network interfaces available on your system

# For more information, see netplan(5).

# vi /etc/netplan/01-netcfg.yaml

        ----------STATIC------------------

network:

 version: 2

 renderer: networkd

 ethernets:

   enp0s3:

     dhcp4: no

     dhcp6: no

     addresses: [192.168.1.110/24]

     gateway4: 192.168.1.1

     nameservers:

       addresses: [8.8.8.8,8.8.4.4]

   -------OR--------

network:

   ethernets:

     eth0:          

     addresses:

     - 192.168.1.9/24

     dhcp: false

     gateway4: 192.168.1.1

     nameservers:

        addresses:

        - 192.168.1.1

        - 8.8.8.8

        - 8.8.4.4

        search: []

  version: 2  

   ----Static 2-------------------------------------------

network:

   ethernets:

     eth0:          

     addresses:

     - 192.168.1.9/24

     dhcp: false

     gateway4: 192.168.1.1

     nameservers:

        addresses:

        - 192.168.1.1

        - 8.8.8.8

        - 8.8.4.4

        search: []

     eth0:

     addresses:

     - 192.168.1.9/24

     dhcp: false

  version: 2  

   ----------------------DHCP------------------

network:

    version: 2

    ethernets:

        enp0s3:

            addresses: []

            dhcp4: true

                  -----OR----

network:

  version: 2

  renderer: networkd

  ethernets:

    enp0s3:

      dhcp4: yes

   -------------------------------------------------------

# $sudo netplan apply

# netplan apply

Set Dynamic DHCP IP Address in Ubuntu

# vim /etc/netplan/01-netcfg.yaml

# This file describes the network interfaces available on your system

# For more information, see netplan(5).

network:

version: 2

renderer: networkd

ethernets:

enp0s8:

dhcp4: yes

dhcp6: yes

Once done save and close the file and apply

$ sudo netplan apply

$ ifconfig -a

sudo ifconfig sudo ip addr show

ip addr show dev enp0s8

sudo netplan --debug apply

systemctl restart NetworkManager.service

service network-manager restart

# systemctl restart systemd-resolved

Make the configuration effective (no reboot needed):

# ifdown --force enp0s3 lo && ifup -a # systemctl unmask networking # systemctl enable networking # systemctl restart networking

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