I have been looking for a way so I can upgrade from
Ubuntu 17.10 to
Ubuntu 18.04 LTS offline.
There were tips in the internet but they were mostly done online.
thanks in advance
First things first: backup, backup, backup!
Back up all of your important data to an external HDD. You could also
dd the entire contents of your internal HDD to an external one if you want a complete 1:1 image of the HDD.
Before you begin, run this command to find out your username:
Now for reinstalling:
Download the Ubuntu 18.04 LTS ISO
Burn the ISO to a DVD, or use the included Startup Disk Creator program to make a live USB drive.
Boot the install media you created in step #2
Choose to install Ubuntu
On the "installation type" screen, choose Something Else
Select Ubuntu system partition, and set its mount point as
/. Be sure to keep the same format type, the same size, and untick the "Format" checkbox (else all data on "/" will be deleted!)
When you are asked to create your username and password, USE THE ONES YOU WROTE DOWN EARLIER!!! (Else loose your data)
After the installation finishes, follow the prompts to shutdown, and remove the installation media when it tells you to.
Reboot and cross your fingers.