Hi,
Any one can guide how to configure AAA server on Linux, which rpm is best (might be "freeradius2.*.*.rpm") . If you know any help full link. I shall be thankful.

Here is an exhaustingly thorough article on building a Radius server on Linux.

What is your distro? It could be that Radius and related packages for your distro already exist in your software sources/repos.

For example, CentOS has the freeradius RPM package. Here is an article that discusses install the packages, along w/some configuration for CentOS and Ubuntu.

In any event, the best way to install an RPM is by using yum, which is a front-end tool for rpm that handles package dependencies/conflicts, etc. for you. Similarly, you'd want to use apt-get instead of dpkg on Ubuntu to install packages.