sudo apt update
Err:1 http://....archive.ubuntu.com/ubuntu zesty InRelease
  Could not resolve '....archive.ubuntu.com'
Hit:2 http://archive.canonical.com/ubuntu zesty InRelease                                 
Hit:3 http://archive.ubuntu.com/ubuntu zesty InRelease                                    
Ign:4 http://archive.ubuntu.com/ubuntu/zesty main InRelease
Ign:5 http://archive.ubuntu.com/ubuntu/zesty-security main InRelease
Ign:6 http://archive.ubuntu.com/ubuntu/zesty-updates main InRelease
Err:7 http://archive.ubuntu.com/ubuntu/zesty main Release
  404  Not Found [IP: 91.189.91.26 80]
Err:8 http://archive.ubuntu.com/ubuntu/zesty-security main Release
  404  Not Found [IP: 91.189.91.26 80]
Err:9 http://archive.ubuntu.com/ubuntu/zesty-updates main Release
  404  Not Found [IP: 91.189.91.26 80]
Reading package lists... Done
E: The repository 'http://archive.ubuntu.com/ubuntu/zesty main Release' does not have a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
E: The repository 'http://archive.ubuntu.com/ubuntu/zesty-security main Release' does not have a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
E: The repository 'http://archive.ubuntu.com/ubuntu/zesty-updates main Release' does not have a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.