Unable to set static address

I have installed ubuntu server and installed LXDE.
LXDE use NetworkManager to manager network interface.
I tried configuring static ip address in /etc/network/interfaces
But after boot IP is not assigned.

what’s the content of /etc/network/interfaces?

content of /etc/network/interfaces

auto lo
iface lo inet loopback

auto eth0
iface eth0 inet static
address 192.168.1.125
netmask 255.255.255.0
gateway 192.168.1.1

Also in /etc/NetworkManager/NetworkManager.conf
is have following lines

[main]
plugins=ifupdown,keyfile

[ifupdown]
managed=false

[keyfile]
unmanaged-devices=interface-name:eth0

Also output of command nmcli dev status

DEVICE  TYPE      STATE         CONNECTION
eth0    ethernet  connected     Wired connection 1
wlan0   wifi      disconnected  --
lo      loopback  unmanaged     --

If its bionic it now uses yaml for networking and its not radxa its your doing it the old and wrong way.
Had to google as had forgot the name “Netplan”

https://www.serverlab.ca/tutorials/linux/administration-linux/how-to-configure-network-settings-in-ubuntu-18-04-bionic-beaver/

I was the same with bionic as spent ages battling with /etc/networking until surprised with a wtf is netplan!
Netplan makes complex networking much easier but actually for simple networking is quite confusing at first as the config for networking is now /etc/netplan/

I don’t know how it started working after I installed netplug package.

While installing this package it installed ifupdown package and it started picking up address from /etc/network/interfaces

1 Like

Yeah not sure how that will work as now it prob has both network services just not defined in Netplan.
You don’t edit /etc/network in ubuntu anymore at least with bionic LTS dunno about later.
They are all yaml’s with numeral prefixes in /etc/netplan prob better having a read of netplan as you got it working but its not how Ubuntu “intended” anymore
https://netplan.io/
/etc/network is still there but is legacy as netplan replaces it