Error while accessing System Updates: Unable to get packages list

Symptoms

• An error is shown while accessing Tools & Settings > System Updates:

  Error: Unable to get packages list: INFO: pum is called with arguments: ['--list', '--repo-info', '--json'] ERROR: ERROR: Exited with returncode 1.

• After clicking Recheck Now button in Tools & Settings > System Updates an error is received:

  Error: Unable to receive update information for the package(s)

• Checking packages with the Plesk CLI utility pum a similar error is received:

  # plesk sbin pum --check
  INFO: pum is called with arguments: ['--check']
  ERROR:
  ERROR: Exited with returncode 1.
  exit status 1

• The following messages can be found in the/var/log/plesk/install/autoinstaller3.logfile:

  Reading package lists...
  W: Target Packages (main/binary-amd64/Packages) is configured multiple times in /etc/apt/sources.list:61 and /etc/apt/sources.list.d/tortix-common.list:1
  W: Target Packages (main/binary-i386/Packages) is configured multiple times in /etc/apt/sources.list:61 and /etc/apt/sources.list.d/tortix-common.list:1
  W: Target Packages (main/binary-all/Packages) is configured multiple times in /etc/apt/sources.list:61 and /etc/apt/sources.list.d/tortix-common.list:1
  W: Target Translations (main/i18n/Translation-en) is configured multiple times in /etc/apt/sources.list:61 and /etc/apt/sources.list.d/tortix-common.list:1
  W: Failed to fetch https://repo.cloudradar.io/dists/all/InRelease Could not resolve 'repo.cloudradar.io'

Cause

Misconfiguration of repositories on the server with duplicated or unresolvable sources are set.

Resolution

1. Connect to the server via SSH

2. Comment the lines with duplicate and/or discontinued repositories from the error messages by prepending the # symbol like below example. Vi editor can be used for this:

   # cat /etc/apt/sources.list.d/cloudradar.list
   #deb https://repo.cloudradar.io all utils

3. Update the package sources with the following command:

   # apt update