Save the Deb package downloaded from Ubuntu apt-Get.

By default, UBUNTU stores the software packages installed through apt-get in the cache folder.

We can back up this folder. If you need to reinstall Ubuntu, you can restore the backup back.

In this way, you cannot connect to the network to update a large number of system software packages.

Install the downloaded Ubuntu apt-Get package

/Var/Cache/APT/Archives

To clear the cache folder, run

Sudo apt-Get clean

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