Linux Ubuntu Server 20.04 LTS: 'Network Unreachable'

I honestly don't have a clue what the issue is as i'm fairly new to Linux and networking. It was working fine for the past month but now it just doesn't want to connect to the internet at all. I've tried to ping my router, 192.168.1.254 and 8.8.8.8 but they both say network unreachable. I tried looking in sudo nano /etc/network/interfaces, but it is just a blank file with nothing in it. Any help is appreciated, thanks.

*-network = DISABLED
description: Ethernet Interface
product: PCI Express Gigabit Ethernet Controller
vendor: Realtek Semiconductor Ltd
physical id: 0
bus info: pci@0000:04:00.0
version: 06
serial: c8:60:00:9e:bf:d1
width: 64 bits
clock: 33mhz
capabilities: pm msi pciexpress msix vpd bus_master cap_list
ethernet_physical
configuration: broadcast=yes driver=r8169 latency=0 link=no multicast=yes
resources: irq:18 ioport:d000(size=256) memory: f0304000-f0304fff memory:
f0300000-f0303fff

that's what comes out when I type in 'sudo lshw -C network'

This is from cat /etc/netplan/*.yaml

network: ethernets: enp7s0: addresses: - 192.168.1.200/24 gateway4: 192.168.1.254 nameservers: addresses: -8.8.8.8 -8.8.4.4 version: 2

Here is what comes out with 'ip a'

1: io: <LOOPBACK.UP.LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN grou 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: enp4s0: <BROADCAST.MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000 link/ether c8:60:00:9e:bf:d1 brd ff:ff:ff:ff:ff:ff

2 Answers

You may have two problems.

.yaml file

Replace your /etc/netplan/*.yaml with my .yaml code. Keep the exact spacing, indentation, and no tabs.

sudo -H gedit /etc/netplan/*.yaml # replace the * with the correct filename

network: version: 2 renderer: networkd ethernets: enp4s0: addresses: - 192.168.1.200/24 gateway4: 192.168.1.254 nameservers: addresses: - 8.8.8.8 - 8.8.4.4

Then do:

sudo netplan generate

sudo netplan apply

reboot # mandatory

link

"link=no" indicates that an ethernet cable may not be attached.

To setup a static ip you need to go to /etc/netplan and there you will see a .yaml file. Check the configs there, otherwise if you have a firewall, it might be that it is blocking you.(It is what happened to me)