will@rain:~$ sudo do-release-upgrade
Checking for a new Ubuntu release
Get:1 Upgrade tool signature [819 B]
Get:2 Upgrade tool [1,243 kB]
Fetched 1,244 kB in 0s (0 B/s)
authenticate 'cosmic.tar.gz' against 'cosmic.tar.gz.gpg'
extracting 'cosmic.tar.gz'

Reading cache

Checking package manager
Reading package lists... Done
Building dependency tree
Reading state information... Done
Ign http://dl.google.com/linux/chrome/deb stable InRelease
Hit http://archive.canonical.com/ubuntu bionic InRelease
Hit http://security.ubuntu.com/ubuntu bionic-security InRelease
Hit https://updates.signal.org/desktop/apt xenial InRelease
Hit http://us.archive.ubuntu.com/ubuntu bionic InRelease
Hit http://repository.spotify.com stable InRelease
Hit http://dl.google.com/linux/chrome/deb stable Release
Hit http://us.archive.ubuntu.com/ubuntu bionic-updates InRelease
Hit https://download.sublimetext.com apt/stable/ InRelease
Hit http://us.archive.ubuntu.com/ubuntu bionic-backports InRelease
Fetched 0 B in 0s (0 B/s)
Reading package lists... Done
Building dependency tree
Reading state information... Done

Updating repository information

Third party sources disabled

Some third party entries in your sources.list were disabled. You can
re-enable them after the upgrade with the 'software-properties' tool
or your package manager.

To continue please press [ENTER]

Fetched 0 B in 0s (0 B/s)

Checking package manager
Reading package lists... Done
Building dependency tree
Reading state information... Done

Invalid package information

After updating your package information, the essential package
'ubuntu-minimal' could not be located. This may be because you have
no official mirrors listed in your software sources, or because of
excessive load on the mirror you are using. See /etc/apt/sources.list
for the current list of configured software sources.
In the case of an overloaded mirror, you may want to try the upgrade
again later.


Restoring original system state

Aborting
Reading package lists... Done
Building dependency tree
Reading state information... Done