Resolution
Since Virtuozzo 3.0 you may update base OS on Virtuozzo server (within the same OS release) like any plain Linux server using native distribution updaters (up2date on Red Hat, yum on Fedora Core, yast on SUSE). All packages that are critical for Virtuozzo and should not be updated are listed in the corresponding exclude lists (for example in Fedora based systems in /etc/yum/swsoft-excludes which is included into /etc/yum.conf).Please do not try to pass force options to native OS updaters to update these packages as this may cause Virtuozzo to malfunction.
So, for example, you may update base Fedora Core OS on Virtuozzo server using 'yum update' command.
Keywords: base OS update, yum, exclude, update