This means your system is at the current state and there are no updates to be installed.
I do not mean to barge in, but we better make sure that this system is updating, the original post states:
After that I notice that every time that I ran yum in server-manager there was never updates
And the last post from Iguzman suggest that nothing has been updated after resetting the repos.
The last lot of updates available are:
php.i386 4.3.9-3.22.9 updates
php-domxml.i386 4.3.9-3.22.9 updates
php-gd.i386 4.3.9-3.22.9 updates
php-imap.i386 4.3.9-3.22.9 updates
php-ldap.i386 4.3.9-3.22.9 updates
php-mbstring.i386 4.3.9-3.22.9 updates
php-mysql.i386 4.3.9-3.22.9 updates
php-pear.i386 4.3.9-3.22.9 updates
xorg-x11-Mesa-libGL.i386 6.8.2-1.EL.31 updates
xorg-x11-libs.i386 6.8.2-1.EL.31 updates
You can check in yum/yum logs if they are there, or run this command from the CL as root:
rpm -qa --last | head -12