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rpm -qi basesystem

Name        : basesystem                   Relocations: (not relocatable)
Version     : 8.0                               Vendor: Red Hat, Inc.
Release     : 5.1.1                         Build Date: Wed 12 Jul 2006 12:38:04 PM IST
Install Date: Mon 03 May 2010 03:05:35 PM IST      Build Host: ls20-bc2-14.build.redhat.com
Group       : System Environment/Base       Source RPM: basesystem-8.0-5.1.1.src.rpm
Size        : 0                                License: public domain
Signature   : DSA/SHA1, Thu 18 Jan 2007 09:03:57 PM IST, Key ID 5326810137017186
Packager    : Red Hat, Inc. <http://bugzilla.redhat.com/bugzilla>
Summary     : The skeleton package which defines a simple Red Hat Linux system.
Description :
Basesystem defines the components of a basic Red Hat Linux system (for
example, the package installation order to use during bootstrapping).
Basesystem should be the first package installed on a system, and it
should never be removed.