The Ubuntu repositories contain thousands of deb packages which can  be installed from the Ubuntu Software Center or by using the apt command line utility. Deb is the installation package format used by  all Debian based distributions including Ubuntu. Some packages are not  available in the standard Ubuntu repositories but it can be easily  installed by enabling the appropriate source.

In most cases when  the software vendor does not provide a repository they will have a  download page from where you can download and install the deb package or  download and compile the software from sources.

Although  not so often, some software may be distributed only as an RPM package.  RPM is a package format used by Red Hat and its derivatives such as  CentOS. Luckily, there is a tool called alien that allows us to install  an RPM file on Ubuntu or to convert an RPM package file into a Debian  package file.

Before you Begin

This  is not the recommended way to install software packages in Ubuntu.  Whenever possible you should prefer installing software from the Ubuntu  repositories.

Not all RPM packages can be installed on Ubuntu. Installing RPM packaged on Ubuntu may lead to package dependency conflicts.

You  should never use this method to replace or update important system  packages, like libc, systemd, or other services and libraries that are  essential for the proper functioning of your system. Doing this may lead  to errors and system instability.

Install Alien

Alien  is a tool that supports conversion between Red Hat rpm, Debian deb,  Stampede slp, Slackware tgz, and Solaris pkg file formats.

Before installing the alien package make sure the Universe repository is enabled on your system:

sudo add-apt-repository universe

Once the repository is enabled update the packages index and install the alien package with:

sudo apt update 

The command above will also install the necessary build tools.

Converting and Installing an RPM package

To convert a package from RPM to DEB format use the alien command followed by the RPM package name:

sudo alien package_name.rpm

Depending  on the package size the conversion may take some time. In most cases,  you will see warning messages printed on your screen. If the package is  successfully converted the output will indicate that the DEB package is  generated:

package_name.deb generated

To install the deb package, you can either use the dpkg or apt utility:

sudo dpkg -i package_name.deb
sudo apt install ./package_name.deb

The package should now be installed, assuming it’s compatible with your system and all dependencies are met.

You’ll need to be logged in as a user with sudo access to be able to install packages on your Ubuntu system.

Installing an RPM package directly

Instead of converting and then installing the package you can use the -i option that will tell alien to install the RPM package directly.

sudo alien -i package_name.rpm

The command above will automatically generate and installed the package and remove the package file after it has been installed.