Using the Red Hat Package Manager
The install mode, as its name suggests, is used to install RPM packages onto your system. Installing a package is accomplished with the -i option:
# rpm -i penguin-3.26.i386.rpm
Before installing the package, RPM performs several checks. First, it makes sure the package you are trying to install isn't already installed. RPM won't let you install a package on top of itself. It also checks that you are not installing an older version of the package. Next, RPM does a dependency check. Some packages depend on other packages being installed first. In this example, you have just downloaded the latest RPM version of Penguin utilities and now want to install it.
# rpm -i penguin-3.26.i386.rpm failed dependencies: iceberg >= 7.1 is needed by penguin-3.26.i386.rpmThis error indicates the penguin package failed to install because it requires the iceberg package with a version equal to or greater than 7.1. You'll have to find and install the iceberg package, and any packages iceberg requires.
Finally, RPM checks to see if any configuration files would be overwritten by the installation of this package. RPM tries to make intelligent decisions about what to do with conflicts. If RPM replaces an existing configuration file with one from the new package, a warning will be printed to the screen.
# rpm -I penguin-3.26.i386.rpm warning: /etc/someconfig saved as /etc/someconfig.rpmsave
It's up to you to look at both files and determine what modifications, if any, need to be made.
The -u switch is used to upgrade existing packages. For example, if Penguin Utilities version 3.25 is already installed, issuing the command
# rpm -u penguin-3.26.i386.rpm
will replace the old version of the package with the new one. In fact, one of the quirks of RPM's upgrade mode is that the older package doesn't have to exist in the first place: -u works identically to -i in this case.
The rpm -e command removes a package from your system. Like Install mode, RPM does some housekeeping before it will let you remove a package. First, it does a dependency check to make sure no other packages depend on the package you are removing. If you have modified any of the configuration files, RPM makes a copy of the file, appends .rpmsave onto the end of it, then erases the original. Finally, after removing all files from your system and the RPM database, it removes the package name from the database.
Be very careful about which packages you remove from your system. Like most Linux utilities, RPM assumes omniscience and will silently let you shoot yourself in the foot. Removing the passwd or kernel package would be devastating.
This has been a basic introduction to the idea of packages and basic package management. You should now have a fairly good idea of how to query, install, upgrade and remove packages from your Linux system.
Kirk Rafferty has been a UNIX System Administrator for twelve years and has been using and maintaining Linux systems for the last five. His hobbies include paintball, gaming and making the best home brew in Colorado. He can be reached for comment at email@example.com.
- The Tiny Internet Project, Part I
- SUSECON 2016: Where Technology Reigns Supreme
- Download "Linux Management with Red Hat Satellite: Measuring Business Impact and ROI"
- Bitcoin on Amazon! Sort of...
- Free Today: September Issue of Linux Journal (Retail value: $5.99)
- Android Browser Security--What You Haven't Been Told
- Securing the Programmer
- Epiq Solutions' Sidekiq M.2
- Machine Learning with Python
Pick up any e-commerce web or mobile app today, and you’ll be holding a mashup of interconnected applications and services from a variety of different providers. For instance, when you connect to Amazon’s e-commerce app, cookies, tags and pixels that are monitored by solutions like Exact Target, BazaarVoice, Bing, Shopzilla, Liveramp and Google Tag Manager track every action you take. You’re presented with special offers and coupons based on your viewing and buying patterns. If you find something you want for your birthday, a third party manages your wish list, which you can share through multiple social- media outlets or email to a friend. When you select something to buy, you find yourself presented with similar items as kind suggestions. And when you finally check out, you’re offered the ability to pay with promo codes, gifts cards, PayPal or a variety of credit cards.Get the Guide