Plesk update failed: RPMDB altered outside of yum

Symptoms

• Installing updates either via Plesk panel or on a command line fails with the following error occurs:

  ERROR: Failed to run the Yum utility.
  The Yum utility failed to install the required packages.
  Attention! Your software might be inoperable.
  Please, contact product technical support.

• There are the following records in /var/log/plesk/install/autoinstaller3.log
file:

  Warning: RPMDB altered outside of yum.
  Exception: Scriptlet or other non-fatal errors occurred during transaction.

  YumDownloadError: [u'Errors were encountered while downloading packages. failure: [Errno 256] No more mirrors to try.']

  ---

  ERROR: Error: rpmdb failed to list provides. Try: rpm --rebuilddb

Cause

Inconsistency between yum and rpmdb.

Resolution

1. Connect to the server via SSH.

   Note: if direct SSH access to the server is not possible, contact server administrator for further assistance.

2. Backup RPM database files:

   # cd /var/lib/rpm/
   # mv __db.* ~

3.  Clear yum cache by following steps below:

   # rm -rf /var/lib/rpm/__db.*

   # rpm --rebuilddb

   # yum clean all

   # yum makecache

4.  Start update again.