My question is: Is there any way to make Ubuntu upgrade offline as in open SUSE ? Ubuntu is suposed to be for newcomers to linux, so I don't know why this happen. The difference between choosing Ubuntu or open SUSE.
I will try your answer @Mr Vaykadji and then I will say the result!
This signature file can be used on another machine connected to the internet (which need not be a Debian box and can even be running windows) to download the updates.
I make many search, I found this question that says using Keryx or Synaptic Manager will do that.A USB repository If you have a decent sized USB stick - assuming around 4-8Gb (or external hard drive) you can set up a custom copy of the Ubuntu repository and configure that as a local repository as covered in Apt Get/Offline/Repository on help.To get the actual package files (the files), I suggest using Only include the repository sections you want. Better still, for those who prefer a GUI, you can also use the Update Manager to update your system with a simple click.Now, what if your Ubuntu computer is not connected to the Internet?Its interface is similar to synaptic, but it works from a pendrive (it doesn't need installation).