# Installation with RPM You can install Class 4 on any Centos environment using RPM. We have RPM for fresh install and update. Each install of Class 4 comes with a forever free 500 ports. If you need more than 500 ports, you can buy license from . ``` yum -y install epel-release yum -y install https://repo.ius.io/ius-release-el7.rpm yum -y install centos-release-scl yum -y install https://download.postgresql.org/pub/repos/yum/reporpms/EL-7-x86_64/pgdg-redhat-repo-latest.noarch.rpm yum install -y https://mirror.webtatic.com/yum/el7/webtatic-release.rpm yum -y install http://repo.denovolab.com/centos/7/noarch/denovolab-1-1.noarch.rpm yum -y install dnl_database yum -y install denovolab-software you're strong enough, save the world: ``` --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://v5cookbook.denovolab.com/installation/installation-with-rpm.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.