[HUB] Plesk Update Manager (PUM) fails: pum is called with arguments

Symptoms

Operations involving package installation or update do not perform as expected and results in the error message which can be found in Plesk interface, /var/log/plesk/panel.log or in the server terminal upon running CLI commands. For example:

Error: Unable to get packages list: 2017-0101 12:00:00 INFO: pum is called with arguments: ['--list', '--repo-info', '--json'] W: There is no public key available for the following key IDs: EF0F382A1AB66500 MarkUpgrade() called on a non-upgradable pkg: 'dpkg' MarkUpgrade() called on a non-upgradable pkg...

Or:

# tail /var/log/plesk/panel.log
ERR [panel] Task failed: id=100, pid=10000, type=pum-update-packages, error=2017-01-01 12:00:00 INFO: pum is called with arguments: ['--update', '--json', '--', 'linux-image-3.16.0-4-amd64', 'linux-libc-dev', ...

Or:

# plesk sbin pum --check
INFO: pum is called with arguments: ['--check']
ERROR: Exited with returncode 100. exit status 100

Cause

In general, issues with Plesk Update Manager caused by the inability of underlying operating system package manager to perform package installation or update.

Troubleshooting

Connect to the server via SSH and run package update manually.

For Debian/Ubuntu:

# apt-get update && apt-get upgrade -y

For RHEL/CentOS/CloudLinux:

# yum update -y

Resolution

Correct repository sources or package dependency issues according to the error message displayed upon the attempt to update packages running APT or YUM.

Note: Resolving issues with the operating system installation consistency is an administrative task.

Known Issues

Plesk Update Manager issues can be split into few categories:

Repository misconfiguration or installation sources unavailability:

• Packages update fails: Failed to fetch URL. Some index files failed to download
• Cannot install system updates via Plesk: [Errno 256] No more mirrors to try
• Packages update fails: Failed to fetch URL. Connection failed
• Information on some packages might not be actual: inconsistencies were detected in the system's package manager database

Broken package dependencies:

• PUM will not perform any update operations until Plesk installation is fixed
• Auto-upgrade of system packages via PUM fails: The following packages were not updated successfully
• If LiteSpeed is used instead of Apache, warning is shown in System Updates: Information on some packages might not be actual
• System updates warning: Information on some packages might not be actual: inconsistencies were detected in the system's package manager database

Several installations or update processes run simultaneously:

• The System Updates does not work: The System Updates tool is already installing updates in automatic mode. Please try later
• Unable to install the Atomic ModSecurity rule set: SLCommon::get_lock Another instance of ASL is running
  

Additional Information

When System Updates (PUM) auto installs available updates in Plesk?