How To Fix No Internet Access After Upgrading to Ubuntu 18.04

After upgrading to a new version of an operating system, it’s not uncommon to encounter a few hiccups. One such issue that many users have reported after upgrading to Ubuntu 18.04 is a lack of internet access. This article will guide you through several potential solutions to this problem.

Understanding the Issue

Before diving into the solutions, it’s important to understand the root of the problem. The issue of no internet access after upgrading to Ubuntu 18.04 can be attributed to a number of factors, including but not limited to, changes in network configuration files, outdated network drivers, or issues with the DNS resolver.

Solution 1: Edit /etc/resolv.conf File

The /etc/resolv.conf file is used to define the DNS servers that your system uses for domain resolution. If this file is not configured correctly, it can lead to internet connectivity issues.

To edit this file, open a terminal and run the following command:

echo "nameserver 8.8.8.8" | sudo tee /etc/resolv.conf > /dev/null

This command uses echo to output the string “nameserver 8.8.8.8”, which is then piped into the sudo tee /etc/resolv.conf command. The tee command is used to write the output to the /etc/resolv.conf file. The > /dev/null part of the command discards the standard output, so it doesn’t clutter your terminal.

If the /etc/resolvconf/resolv.conf.d/head file is empty, run the following command:

echo "nameserver 8.8.8.8" | sudo tee -a /etc/resolvconf/resolv.conf.d/head > /dev/null

This command appends the “nameserver 8.8.8.8” line to the head file.

Finally, restart the resolvconf and networking services with these commands:

sudo systemctl enable resolvconf
sudo systemctl start resolvconf
sudo /etc/init.d/networking restart

Solution 2: Edit /etc/systemd/resolved.conf File

The /etc/systemd/resolved.conf file is used by the systemd-resolved service to configure network parameters. You can add the DNS servers directly to this file.

Open the file with a text editor using the following command:

sudo vim /etc/systemd/resolved.conf

Then, add the following line to the file:

DNS=8.8.8.8

Save the file and reboot your system to apply the changes.

Solution 3: Edit /etc/network/interfaces File

The /etc/network/interfaces file is used to configure network interfaces. You can manually define your Ethernet interface in this file to fix the internet connectivity issue.

Open the file with a text editor using the following command:

sudo gedit /etc/network/interfaces

Then, add the following lines to the file, replacing eth1 with the name of your Ethernet interface:

auto eth1
iface eth1 inet dhcp

The auto keyword is used to automatically start the network interface when the system boots. The iface line defines the interface and sets it to use DHCP for IP address assignment.

After editing the file, use the following command to bring up the interface:

sudo ifup eth1

Finally, reboot your system to apply the changes.

Solution 4: Edit /etc/resolvconf/resolv.conf.d/base File

The /etc/resolvconf/resolv.conf.d/base file is used to define the base configuration for the resolv.conf file. You can add the DNS servers directly to this file.

Open the file with a text editor using the following command:

sudo vim /etc/resolvconf/resolv.conf.d/base

Then, add the following lines to the file:

nameserver 8.8.8.8
nameserver 8.8.4.4

These lines define the primary and secondary DNS servers that your system will use for domain resolution.

Save the file and reboot your system to apply the changes.

Solution 5: Reinstall Network Driver

In some cases, the issue might be due to an outdated or incompatible network driver. In such cases, reinstalling the network driver might solve the problem.

First, download the appropriate network driver for your system from the Intel website. Extract the downloaded file and navigate to the src directory.

Compile the driver module using the command:

make install

If you encounter an error related to skb_frag_off, comment out the function in the src/kcompat.h file and run make install again.

Finally, load the driver module using the commands:

modinfo e1000e
modprobe e1000e [parameter=port1_value,port2_value]

The modinfo command is used to display information about a kernel module, in this case, e1000e. The modprobe command is used to add a module to the Linux kernel.

Conclusion

These are some of the potential solutions to the issue of no internet access after upgrading to Ubuntu 18.04. Please note that these solutions have been suggested by users and may not work for everyone. It is recommended to try them one by one and see which one resolves the internet connectivity issue after the upgrade. If none of these solutions work, it might be worth reaching out to the Ubuntu community or seeking professional help.