What are these file formats and how do they differ from the
.msi format in Windows? Also what are the pros and cons of these package management schemes?
Files such as
.rpm are more akin to a
.zip file. They're a directory tree of files and sub-directories that contain files related to a particular application and/or library of files.
.deb files are meant for distributions of Linux that derive from Debian (Ubuntu, Linux Mint, etc.). The
.rpm files are used primarily by distributions that derive from Redhat based distros (Fedora, CentOS, RHEL) as well as by the openSuSE distro.
What's special about them?
These files have one other special trait that sets them apart from
.zip files, in that they can include a specification that contains rules that tell the package manager software running on a system that's installing one of these files to do additional tasks. These tasks would include things such as:
- creating user accounts on the system
- creating/modifying configuration files that aren't actually contained in the
- set ownership/permissions on the files after installation
- run commands as root on the system that's installing the package
- dependencies, both formats can include names or packages and/or service names that they require to be present on a system, prior to installation.
What about .msi files?
.msi files are similar to
.rpm files but likely even more sophisticated. The
.msi files are utilized by the Windows Installer and offer additional features such as:
- GUI Framework
- generation of uninstall sequences
- A framework within itself - for use by 3rd party installers
- User Interface
I'd suggest taking a look at the various Wikipedia pages on these subjects if you want a more in-depth explanation.
The other answers touch upon qualities of
.rpm that are similar to
.msi. They all contain software in a compressed format that can do some extra things. Those extra things already mentioned included adding users, pre- and post-install tasks, registering the program with the system (e.g. windows registry, xdg-dirs, OpenRC/systemd init, etc).
What differentiates the formats (and is a huge pro) is dependencies. Both
.rpm files can and do list names and versions of other programs that must be installed as pre-requisite software. By themselves, this is just informational, but...
You typically do not directly interact with
.rpm files the way you do with
.msi files. In fact, as alluded to earlier, a
.deb is typically just an archive (ar or tar) compressed with xz with the contained files in a specific directory layout. Instead you use tools like
rpm to manipulate these files.
rpm will install the contents of
.rpm files and verify all pre-requisite software is installed. Running these programs is similar to clicking on a
.msi file. Users however, do not typically interact with
rpm but instead use
yum to install packages. These tools do not have exact analogs on windows.
yum are able to fetch files from remote (or local) repositories and use the dependency information stored in the
.rpm files to fetch and install any pre-requisites not met. With these tools I do not need to know or worry about what other software I need, I can just specify
apt-get install chromium and know that
apt-get will make sure I have gtk+, alsa, certain X libraries, etc installed without me having to manually find and install those
yum are the big two package managers, you'll also find
pacman out there, which do the same jobs although with different underlying mechanisms.
It has quite the same functionalities as an MSI file under Windows :
- it registers the software in a registry,
- it registers which files have been installed with that package.
Under Linux, they also manage dependencies between other packages.
This package managment formats do many other things, but this is the main functionalities.
.rpm files are RPM packages, which refer to the package type used by Red Hat and Red Hat-derived distros (e.g. Fedora, RHEL, CentOS).
.deb files are DEB packages, which are the package type used by Debian and Debian-derivatives (e.g. Debian, Ubuntu).
When downloaded, they are typically installed via the
dpkg commands respectively on the relevant distros. In other words, they are files that are installed by
dpkg rather than
.exe setup files which are executables that install themselves.
RPM and DEB packages differ from MSI in multiple ways.
- As above, they are files that require other tools (i.e.
dpkg) to install.
- When installed, they are added to a database, which is not the case in MSI files. MSI files list the program in the registry, but an uninstall by Control Panel is unlikely to completely remove all installed files from disk. Thus, when RPM and DEB packages are uninstalled, all files are removed cleanly.
- They are typically not downloaded and installed directly, but through package managers like
aptituderespectively - there are so-called repositories that offer packages compiled for the relevant system, and the package manager will install all dependencies automatically from data in the repositories.
- Installed packages typically run several configuration tools, for example if you install GDM on a system already installed with LightDM, the tools ask if you would prefer to use GDM of LightDM.
- When installing packages, other than dependencies some packages are suggested, which show packages not required but may be useful to the user.
.rpm are Software packages for GNU/Linux Distributions, containing software (program(s), application(s), etc.) and information for the "*installer *" software about the software itself and instructions about how to install what and where correctly.
.deb→ Debian Software Package, on Debian (based) Distributions. Installed through e.g.
aptitude(Command line), or graphically via e.g. "Synaptic" "Ubuntu Software Center", "Gdebi", …
.rpm→ Red Hat Package Manager: in Fedora / Red Hat (based) Linux Distributions. Installed via e.g.
yum(command line), or graphically via e.g. "yumex"
.msiis → Microsoft Installer: Quite the same as above, for Microsoft Windows OS
The installers themselves can also handle maintenance, updating and/or removal of packages. Also: here, "installer" means the software to accomplish this tasks correctly – it also provides the mentioned information for user itself, of course, to accomplish such tasks manually.