Chapter 9. Yum
Yum is the Red Hat package manager that is able to query for information about available packages, fetch packages from repositories, install and uninstall them, and update an entire system to the latest available version. Yum performs automatic dependency resolution when updating, installing, or removing packages, and thus is able to automatically determine, fetch, and install all available dependent packages.
Yum can be configured with new, additional repositories, or package sources, and also provides many plug-ins which enhance and extend its capabilities. Yum is able to perform many of the same tasks that RPM can; additionally, many of the command-line options are similar. Yum enables easy and simple package management on a single machine or on groups of them.
The following sections assume your system was registered with Red Hat Subscription Management during installation as described in the Red Hat Enterprise Linux 7 Installation Guide. If your system is not subscribed, see Chapter 7, Registering the System and Managing Subscriptions.
Yum provides secure package management by enabling GPG (Gnu Privacy Guard; also known as GnuPG) signature verification on GPG-signed packages to be turned on for all package repositories (package sources), or for individual repositories. When signature verification is enabled, yum will refuse to install any packages not GPG-signed with the correct key for that repository. This means that you can trust that the RPM packages you download and install on your system are from a trusted source, such as Red Hat, and were not modified during transfer. See Section 9.5, “Configuring Yum and Yum Repositories” for details on enabling signature-checking with yum.
Yum also enables you to easily set up your own repositories of RPM packages for download and installation on other machines. When possible, yum uses parallel download of multiple packages and metadata to speed up downloading.
Learning yum is a worthwhile investment because it is often the fastest way to perform system administration tasks, and it provides capabilities beyond those provided by the PackageKit graphical package management tools.
You must have superuser privileges in order to use yum to install, update or remove packages on your system. All examples in this chapter assume that you have already obtained superuser privileges by using either the
9.1. Checking For and Updating Packages
Yum enables you to check if your system has any updates waiting to be applied. You can list packages that need to be updated and update them as a whole, or you can update a selected individual package.
9.1.1. Checking For Updates
To see which installed packages on your system have updates available, use the following command:
Example 9.1. Example output of the yum check-update command
The output of
check-update can look as follows:
~]# yum check-update Loaded plugins: product-id, search-disabled-repos, subscription-manager dracut.x86_64 033-360.el7_2 rhel-7-server-rpms dracut-config-rescue.x86_64 033-360.el7_2 rhel-7-server-rpms kernel.x86_64 3.10.0-327.el7 rhel-7-server-rpms rpm.x86_64 4.11.3-17.el7 rhel-7-server-rpms rpm-libs.x86_64 4.11.3-17.el7 rhel-7-server-rpms rpm-python.x86_64 4.11.3-17.el7 rhel-7-server-rpms yum.noarch 3.4.3-132.el7 rhel-7-server-rpms
The packages in the above output are listed as having updates available. The first package in the list is dracut. Each line in the example output consists of several rows, in case of dracut:
dracut— the name of the package,
x86_64— the CPU architecture the package was built for,
033— the version of the updated package to be installed,
360.el7— the release of the updated package,
_2— a build version, added as part of a z-stream update,
rhel-7-server-rpms— the repository in which the updated package is located.
The output also shows that we can update the kernel (the kernel package), yum and RPM themselves (the yum and rpm packages), as well as their dependencies (such as the rpm-libs, and rpm-python packages), all using the
9.1.2. Updating Packages
You can choose to update a single package, multiple packages, or all packages at once. If any dependencies of the package or packages you update have updates available themselves, then they are updated too.
Updating a Single Package
To update a single package, run the following command as
yum update package_name
Example 9.2. Updating the rpm package
To update the rpm package, type:
~]# yum update rpm Loaded plugins: langpacks, product-id, subscription-manager Updating Red Hat repositories. INFO:rhsm-app.repolib:repos updated: 0 Setting up Update Process Resolving Dependencies --> Running transaction check ---> Package rpm.x86_64 0:4.11.1-3.el7 will be updated --> Processing Dependency: rpm = 4.11.1-3.el7 for package: rpm-libs-4.11.1-3.el7.x86_64 --> Processing Dependency: rpm = 4.11.1-3.el7 for package: rpm-python-4.11.1-3.el7.x86_64 --> Processing Dependency: rpm = 4.11.1-3.el7 for package: rpm-build-4.11.1-3.el7.x86_64 ---> Package rpm.x86_64 0:4.11.2-2.el7 will be an update --> Running transaction check ... --> Finished Dependency Resolution Dependencies Resolved ============================================================================= Package Arch Version Repository Size ============================================================================= Updating: rpm x86_64 4.11.2-2.el7 rhel 1.1 M Updating for dependencies: rpm-build x86_64 4.11.2-2.el7 rhel 139 k rpm-build-libs x86_64 4.11.2-2.el7 rhel 98 k rpm-libs x86_64 4.11.2-2.el7 rhel 261 k rpm-python x86_64 4.11.2-2.el7 rhel 74 k Transaction Summary ============================================================================= Upgrade 1 Package (+4 Dependent packages) Total size: 1.7 M Is this ok [y/d/N]:
This output contains several items of interest:
Loaded plugins: langpacks, product-id, subscription-manager— Yum always informs you which yum plug-ins are installed and enabled. See Section 9.6, “Yum Plug-ins” for general information on yum plug-ins, or Section 9.6.3, “Working with Yum Plug-ins” for descriptions of specific plug-ins.
rpm.x86_64— you can download and install a new rpm package as well as its dependencies. Transaction check is performed for each of these packages.
Yum presents the update information and then prompts you for confirmation of the update; yum runs interactively by default. If you already know which transactions the
yumcommand plans to perform, you can use the
-yoption to automatically answer
yesto any questions that yum asks (in which case it runs non-interactively). However, you should always examine which changes yum plans to make to the system so that you can easily troubleshoot any problems that might arise. You can also choose to download the package without installing it. To do so, select the
doption at the download prompt. This launches a background download of the selected package.
If a transaction fails, you can view yum transaction history by using the
yum historycommand as described in Section 9.4, “Working with Transaction History”.
Yum always installs a new kernel regardless of whether you are using the
yum update or
yum install command.
When using RPM, on the other hand, it is important to use the
rpm -i kernel command which installs a new kernel instead of
rpm -u kernel which replaces the current kernel.
Similarly, it is possible to update a package group. Type as
yum group update group_name
Here, replace group_name with a name of the package group you want to update. For more information on package groups, see Section 9.3, “Working with Package Groups”.
Yum also offers the
upgrade command that is equal to
update with enabled
obsoletes configuration option (see Section 9.5.1, “Setting [main] Options”). By default,
obsoletes is turned on in
/etc/yum.conf, which makes these two commands equivalent.
Updating All Packages and Their Dependencies
To update all packages and their dependencies, use the
yum update command without any arguments:
Updating Security-Related Packages
If packages have security updates available, you can update only these packages to their latest versions. Type as
yum update --security
You can also update packages only to versions containing the latest security updates. Type as
yum update-minimal --security
For example, assume that:
- the kernel-3.10.0-1 package is installed on your system;
- the kernel-3.10.0-2 package was released as a security update;
- the kernel-3.10.0-3 package was released as a bug fix update.
yum update-minimal --security updates the package to kernel-3.10.0-2, and
yum update --security updates the package to kernel-3.10.0-3.
Automating Package Updating
To refresh the package database and download updates automatically, you can use the
yum-cron service. For more information, see Section 9.7, “Automatically Refreshing Package Database and Downloading Updates with Yum-cron”.
9.1.3. Upgrading the System Off-line with ISO and Yum
For systems that are disconnected from the Internet or Red Hat Network, using the
yum update command with the Red Hat Enterprise Linux installation ISO image is an easy and quick way to upgrade systems to the latest minor version. The following steps illustrate the upgrading process:
Create a target directory to mount your ISO image. This directory is not automatically created when mounting, so create it before proceeding to the next step. As
Replace mount_dir with a path to the mount directory. Typically, users create it as a subdirectory in the
Mount the Red Hat Enterprise Linux 7 installation ISO image to the previously created target directory. As
mount -o loop iso_name mount_dir
Replace iso_name with a path to your ISO image and mount_dir with a path to the target directory. Here, the
loopoption is required to mount the file as a block device.
media.repofile from the mount directory to the
/etc/yum.repos.d/directory. Note that configuration files in this directory must have the .repo extension to function properly.
This creates a configuration file for the yum repository. Replace new.repo with the filename, for example rhel7.repo.
Edit the new configuration file so that it points to the Red Hat Enterprise Linux installation ISO. Add the following line into the
Replace mount_dir with a path to the mount point.
Update all yum repositories including
/etc/yum.repos.d/new.repocreated in previous steps. As
This upgrades your system to the version provided by the mounted ISO image.
After successful upgrade, you can unmount the ISO image. As
where mount_dir is a path to your mount directory. Also, you can remove the mount directory created in the first step. As
If you will not use the previously created configuration file for another installation or update, you can remove it. As
Example 9.3. Upgrading from Red Hat Enterprise Linux 7.0 to 7.1
If required to upgrade a system without access to the Internet using an ISO image with the newer version of the system, called for example
rhel-server-7.1-x86_64-dvd.iso, create a target directory for mounting, such as
root, change into the directory with your ISO image and type:
~]# mount -o loop
Then set up a yum repository for your image by copying the
media.repo file from the mount directory:
To make yum recognize the mount point as a repository, add the following line into the
/etc/yum.repos.d/rhel7.repo copied in the previous step:
Now, updating the yum repository will upgrade your system to a version provided by
~]# yum update
When your system is successfully upgraded, you can unmount the image, remove the target directory and the configuration file:
9.2. Working with Packages
Yum enables you to perform a complete set of operations with software packages, including searching for packages, viewing information about them, installing and removing.
9.2.1. Searching Packages
You can search all RPM package names, descriptions and summaries by using the following command:
Replace term with a package name you want to search.
Example 9.4. Searching for packages matching a specific string
To list all packages that match "vim", "gvim", or "emacs", type:
~]$ yum search vim gvim emacs Loaded plugins: langpacks, product-id, search-disabled-repos, subscription-manager ============================= N/S matched: vim ============================== vim-X11.x86_64 : The VIM version of the vi editor for the X Window System vim-common.x86_64 : The common files needed by any version of the VIM editor [output truncated] ============================ N/S matched: emacs ============================= emacs.x86_64 : GNU Emacs text editor emacs-auctex.noarch : Enhanced TeX modes for Emacs [output truncated] Name and summary matches mostly, use "search all" for everything. Warning: No matches found for: gvim
yum search command is useful for searching for packages you do not know the name of, but for which you know a related term. Note that by default,
yum search returns matches in package name and summary, which makes the search faster. Use the
yum search all command for a more exhaustive but slower search.
Filtering the Results
All of yum’s list commands allow you to filter the results by appending one or more glob expressions as arguments. Glob expressions are normal strings of characters which contain one or more of the wildcard characters
* (which expands to match any character subset) and
? (which expands to match any single character).
Be careful to escape the glob expressions when passing them as arguments to a
yum command, otherwise the Bash shell will interpret these expressions as pathname expansions, and potentially pass all files in the current directory that match the global expressions to
yum. To make sure the glob expressions are passed to
yum as intended, use one of the following methods:
- escape the wildcard characters by preceding them with a backslash character
- double-quote or single-quote the entire glob expression.
Examples in the following section demonstrate usage of both these methods.
9.2.2. Listing Packages
To list information on all installed and available packages type the following at a shell prompt:
To list installed and available packages that match inserted glob expressions use the following command:
yum list glob_expression…
Example 9.5. Listing ABRT-related packages
Packages with various ABRT add-ons and plug-ins either begin with "abrt-addon-", or "abrt-plugin-". To list these packages, type the following command at a shell prompt. Note how the wildcard characters are escaped with a backslash character:
~]$ yum list abrt-addon\* abrt-plugin\* Loaded plugins: langpacks, product-id, search-disabled-repos, subscription-manager Installed Packages abrt-addon-ccpp.x86_64 2.1.11-35.el7 @rhel-7-server-rpms abrt-addon-kerneloops.x86_64 2.1.11-35.el7 @rhel-7-server-rpms abrt-addon-pstoreoops.x86_64 2.1.11-35.el7 @rhel-7-server-rpms abrt-addon-python.x86_64 2.1.11-35.el7 @rhel-7-server-rpms abrt-addon-vmcore.x86_64 2.1.11-35.el7 @rhel-7-server-rpms abrt-addon-xorg.x86_64 2.1.11-35.el7 @rhel-7-server-rpms
To list all packages installed on your system use the
installed keyword. The rightmost column in the output lists the repository from which the package was retrieved.
yum list installed glob_expression…
Example 9.6. Listing all installed versions of the krb package
The following example shows how to list all installed packages that begin with "krb" followed by exactly one character and a hyphen. This is useful when you want to list all versions of certain component as these are distinguished by numbers. The entire glob expression is quoted to ensure proper processing.
~]$ yum list installed "krb?-*" Loaded plugins: langpacks, product-id, search-disabled-repos, subscription-manager Installed Packages krb5-libs.x86_64 1.13.2-10.el7 @rhel-7-server-rpms
To list all packages in all enabled repositories that are available to install, use the command in the following form:
yum list available glob_expression…
Example 9.7. Listing available gstreamer plug-ins
For instance, to list all available packages with names that contain "gstreamer" and then "plugin", run the following command:
~]$ yum list available gstreamer*plugin\* Loaded plugins: langpacks, product-id, search-disabled-repos, subscription-manager Available Packages gstreamer-plugins-bad-free.i686 0.10.23-20.el7 rhel-7-server-rpms gstreamer-plugins-base.i686 0.10.36-10.el7 rhel-7-server-rpms gstreamer-plugins-good.i686 0.10.31-11.el7 rhel-7-server-rpms gstreamer1-plugins-bad-free.i686 1.4.5-3.el7 rhel-7-server-rpms gstreamer1-plugins-base.i686 1.4.5-2.el7 rhel-7-server-rpms gstreamer1-plugins-base-devel.i686 1.4.5-2.el7 rhel-7-server-rpms gstreamer1-plugins-base-devel.x86_64 1.4.5-2.el7 rhel-7-server-rpms gstreamer1-plugins-good.i686 1.4.5-2.el7 rhel-7-server-rpms
To list the repository ID, name, and number of packages for each enabled repository on your system, use the following command:
To list more information about these repositories, add the
-v option. With this option enabled, information including the file name, overall size, date of the last update, and base URL are displayed for each listed repository. As an alternative, you can use the
repoinfo command that produces the same output.
To list both enabled and disabled repositories use the following command. A status column is added to the output list to show which of the repositories are enabled.
disabled as a first argument, you can reduce the command output to disabled repositories. For further specification you can pass the ID or name of repositories or related glob_expressions as arguments. Note that if there is an exact match between the repository ID or name and the inserted argument, this repository is listed even if it does not pass the enabled or disabled filter.
9.2.3. Displaying Package Information
To display information about one or more packages, use the following command (glob expressions are valid here as well):
yum info package_name…
Replace package_name with the name of the package.
Example 9.8. Displaying information on the abrt package
To display information about the abrt package, type:
~]$ yum info abrt Loaded plugins: langpacks, product-id, search-disabled-repos, subscription-manager Installed Packages Name : abrt Arch : x86_64 Version : 2.1.11 Release : 35.el7 Size : 2.3 M Repo : installed From repo : rhel-7-server-rpms Summary : Automatic bug detection and reporting tool URL : https://fedorahosted.org/abrt/ License : GPLv2+ Description : abrt is a tool to help users to detect defects in applications and : to create a bug report with all information needed by maintainer to fix : it. It uses plugin system to extend its functionality.
yum info package_name command is similar to the
rpm -q --info package_name command, but provides as additional information the name of the yum repository the RPM package was installed from (look for the
From repo: line in the output).
You can also query the yum database for alternative and useful information about a package by using the following command:
yumdb info package_name
This command provides additional information about a package, including the check sum of the package (and the algorithm used to produce it, such as SHA-256), the command given on the command line that was invoked to install the package (if any), and the reason why the package is installed on the system (where
user indicates it was installed by the user, and
dep means it was brought in as a dependency).
Example 9.9. Querying yumdb for information on the yum package
To display additional information about the yum package, type:
~]$ yumdb info yum Loaded plugins: langpacks, product-id yum-3.4.3-132.el7.noarch changed_by = 1000 checksum_data = a9d0510e2ff0d04d04476c693c0313a11379053928efd29561f9a837b3d9eb02 checksum_type = sha256 command_line = upgrade from_repo = rhel-7-server-rpms from_repo_revision = 1449144806 from_repo_timestamp = 1449144805 installed_by = 4294967295 origin_url = https://cdn.redhat.com/content/dist/rhel/server/7/7Server/x86_64/os/Packages/yum-3.4.3-132.el7.noarch.rpm reason = user releasever = 7Server var_uuid = 147a7d49-b60a-429f-8d8f-3edb6ce6f4a1
For more information on the
yumdb command, see the yumdb(8) manual page.
9.2.4. Installing Packages
To install a single package and all of its non-installed dependencies, enter a command in the following form as
yum install package_name
You can also install multiple packages simultaneously by appending their names as arguments. To do so, type as
yum install package_name package_name…
If you are installing packages on a multilib system, such as an AMD64 or Intel 64 machine, you can specify the architecture of the package (as long as it is available in an enabled repository) by appending .arch to the package name:
yum install package_name.arch
Example 9.10. Installing packages on multilib system
To install the sqlite package for the
i686 architecture, type:
~]# yum install
You can use glob expressions to quickly install multiple similarly named packages. Execute as
yum install glob_expression…
Example 9.11. Installing all audacious plugins
Global expressions are useful when you want to install several packages with similar names. To install all audacious plug-ins, use the command in the following form:
~]# yum install
In addition to package names and glob expressions, you can also provide file names to
yum install. If you know the name of the binary you want to install, but not its package name, you can give
yum install the path name. As
yum install /usr/sbin/named
Yum then searches through its package lists, finds the package which provides
/usr/sbin/named, if any, and prompts you as to whether you want to install it.
As you can see in the above examples, the
yum install command does not require strictly defined arguments. It can process various formats of package names and glob expressions, which makes installation easier for users. On the other hand, it takes some time until yum parses the input correctly, especially if you specify a large number of packages. To optimize the package search, you can use the following commands to explicitly define how to parse the arguments:
install-n, yum interprets name as the exact name of the package. The
install-na command tells yum that the subsequent argument contains the package name and architecture divided by the dot character. With
install-nevra, yum will expect an argument in the form name-epoch:version-release.architecture. Similarly, you can use
yum remove-na, and
yum remove-nevra when searching for packages to be removed.
If you know you want to install the package that contains the
named binary, but you do not know in which
sbin/ directory the file is installed, use the
yum provides command with a glob expression:
~]# yum provides "*bin/named" Loaded plugins: langpacks, product-id, search-disabled-repos, subscription- : manager 32:bind-9.9.4-14.el7.x86_64 : The Berkeley Internet Name Domain (BIND) DNS : (Domain Name System) server Repo : rhel-7-server-rpms Matched from: Filename : /usr/sbin/named
yum provides "*/file_name" is a useful way to find the packages that contain file_name.
Example 9.12. Installation Process
The following example provides an overview of installation with use of yum. To download and install the latest version of the httpd package, execute as
~]# yum install httpd Loaded plugins: langpacks, product-id, subscription-manager Resolving Dependencies --> Running transaction check ---> Package httpd.x86_64 0:2.4.6-12.el7 will be updated ---> Package httpd.x86_64 0:2.4.6-13.el7 will be an update --> Processing Dependency: 2.4.6-13.el7 for package: httpd-2.4.6-13.el7.x86_64 --> Running transaction check ---> Package httpd-tools.x86_64 0:2.4.6-12.el7 will be updated ---> Package httpd-tools.x86_64 0:2.4.6-13.el7 will be an update --> Finished Dependency Resolution Dependencies Resolved
After executing the above command, yum loads the necessary plug-ins and runs the transaction check. In this case, httpd is already installed. Since the installed package is older than the latest currently available version, it will be updated. The same applies to the httpd-tools package that httpd depends on. Then, a transaction summary is displayed:
================================================================================ Package Arch Version Repository Size ================================================================================ Updating: httpd x86_64 2.4.6-13.el7 rhel-x86_64-server-7 1.2 M Updating for dependencies: httpd-tools x86_64 2.4.6-13.el7 rhel-x86_64-server-7 77 k Transaction Summary ================================================================================ Upgrade 1 Package (+1 Dependent package) Total size: 1.2 M Is this ok [y/d/N]:
In this step yum prompts you to confirm the installation. Apart from
y (yes) and
N (no) options, you can choose
d (download only) to download the packages but not to install them directly. If you choose
y, the installation proceeds with the following messages until it is finished successfully.
Downloading packages: Running transaction check Running transaction test Transaction test succeeded Running transaction Updating : httpd-tools-2.4.6-13.el7.x86_64 1/4 Updating : httpd-2.4.6-13.el7.x86_64 2/4 Cleanup : httpd-2.4.6-12.el7.x86_64 3/4 Cleanup : httpd-tools-2.4.6-12.el7.x86_64 4/4 Verifying : httpd-2.4.6-13.el7.x86_64 1/4 Verifying : httpd-tools-2.4.6-13.el7.x86_64 2/4 Verifying : httpd-tools-2.4.6-12.el7.x86_64 3/4 Verifying : httpd-2.4.6-12.el7.x86_64 4/4 Updated: httpd.x86_64 0:2.4.6-13.el7 Dependency Updated: httpd-tools.x86_64 0:2.4.6-13.el7 Complete!
To install a previously downloaded package from the local directory on your system, use the following command:
Replace path with the path to the package you want to install.
9.2.5. Downloading Packages
As shown in Example 9.12, “Installation Process”, at a certain point of installation process you are prompted to confirm the installation with the following message:
... Total size: 1.2 M Is this ok [y/d/N]: ...
d option, yum downloads the packages without installing them immediately. You can install these packages later offline with the
yum localinstall command or you can share them with a different device. Downloaded packages are saved in one of the subdirectories of the cache directory, by default
/var/cache/yum/$basearch/$releasever/packages/. The downloading proceeds in background mode so that you can use yum for other operations in parallel.
9.2.6. Removing Packages
Similarly to package installation, yum enables you to uninstall them. To uninstall a particular package, as well as any packages that depend on it, run the following command as
yum remove package_name…
As when you install multiple packages, you can remove several at once by adding more package names to the command.
Example 9.13. Removing several packages
To remove totem, type the following at a shell prompt:
~]# yum remove totem
remove can take these arguments:
- package names
- glob expressions
- file lists
- package provides
Yum is not able to remove a package without also removing packages which depend on it. This type of operation, which can only be performed by RPM, is not advised, and can potentially leave your system in a non-functioning state or cause applications to not work correctly or crash.
9.3. Working with Package Groups
A package group is a collection of packages that serve a common purpose, for instance System Tools or Sound and Video. Installing a package group pulls a set of dependent packages, saving time considerably. The
yum groups command is a top-level command that covers all the operations that act on package groups in yum.
9.3.1. Listing Package Groups
summary option is used to view the number of installed groups, available groups, available environment groups, and both installed and available language groups:
Example 9.14. Example output of yum groups summary
summaryLoaded plugins: langpacks, product-id, subscription-manager Available Environment Groups: 12 Installed Groups: 10 Available Groups: 12
To list all package groups from yum repositories add the
list option. You can filter the command output by group names.
yum group list glob_expression…
Several optional arguments can be passed to this command, including
hidden to list also groups not marked as user visible, and
ids to list group IDs. You can add
available options to reduce the command output to a specific group type.
To list mandatory and optional packages contained in a particular group, use the following command:
yum group info glob_expression…
Example 9.15. Viewing information on the LibreOffice package group
~]$ yum group info
LibreOfficeLoaded plugins: langpacks, product-id, subscription-manager Group: LibreOffice Group-Id: libreoffice Description: LibreOffice Productivity Suite Mandatory Packages: =libreoffice-calc libreoffice-draw -libreoffice-emailmerge libreoffice-graphicfilter =libreoffice-impress =libreoffice-math =libreoffice-writer +libreoffice-xsltfilter Optional Packages: libreoffice-base libreoffice-pyuno
As you can see in the above example, the packages included in the package group can have different states that are marked with the following symbols:
-" — Package is not installed and it will not be installed as a part of the package group.
+" — Package is not installed but it will be installed on the next
yum group upgrade.
=" — Package is installed and it was installed as a part of the package group.
no symbol — Package is installed but it was installed outside of the package group. This means that the
yum group removewill not remove these packages.
These distinctions take place only when the
group_command configuration parameter is set to
objects, which is the default setting. Set this parameter to a different value if you do not want yum to track if a package was installed as a part of the group or separately, which will make "no symbol" packages equivalent to "=" packages.
You can alter the above package states using the
yum group mark command. For example,
yum group mark packages marks any given installed packages as members of a specified group. To avoid installation of new packages on group update, use
yum group mark blacklist. See the
yum(8) man page for more information on capabilities of
yum group mark.
You can identify an environmental group with use of the @^ prefix and a package group can be marked with @. When using
remove, pass @group_name to specify a package group, @^group_name to specify an environmental group, or group_name to include both.
9.3.2. Installing a Package Group
Each package group has a name and a group ID (groupid). To list the names of all package groups, and their group IDs, which are displayed in parentheses, type:
yum group list ids
Example 9.16. Finding name and groupid of a package group
To find the name or ID of a package group, for example a group related to the KDE desktop environment, type:
~]$ yum group list ids kde\* Available environment groups: KDE Plasma Workspaces (kde-desktop-environment) Done
Some groups are hidden by settings in the configured repositories. For example, on a server, make use of the
hidden command option to list hidden groups too:
~]$ yum group list hidden ids kde\* Loaded plugins: product-id, subscription-manager Available Groups: KDE (kde-desktop) Done
You can install a package group by passing its full group name, without the groupid part, to the
group install command. As
group install"group name"
You can also install by groupid. As
root, execute the following command:
You can pass the groupid or quoted group name to the
install command if you prepend it with an @ symbol, which tells
yum that you want to perform
group install. As
Replace group with the groupid or quoted group name. The same logic applies to environmental groups:
yum install @^group
Example 9.17. Four equivalent ways of installing the KDE Desktop group
As mentioned before, you can use four alternative, but equivalent ways to install a package group. For KDE Desktop, the commands look as follows:
~]# yum group install "KDE Desktop" ~]# yum group install kde-desktop ~]# yum install @"KDE Desktop" ~]# yum install @kde-desktop
9.3.3. Removing a Package Group
You can remove a package group using syntax similar to the
install syntax, with use of either name of the package group or its id. As
yum group remove group_name
Also, you can pass the groupid or quoted name to the
remove command if you prepend it with an @-symbol, which tells yum that you want to perform
group remove. As
Replace group with the groupid or quoted group name. Similarly, you can replace an environmental group:
yum remove @^group
Example 9.18. Four equivalent ways of removing the
KDE Desktop group
Similarly to install, you can use four alternative, but equivalent ways to remove a package group. For KDE Desktop, the commands look as follows:
~]# yum group remove "KDE Desktop" ~]# yum group remove kde-desktop ~]# yum remove @"KDE Desktop" ~]# yum remove @kde-desktop
9.4. Working with Transaction History
yum history command enables users to review information about a timeline of yum transactions, the dates and times they occurred, the number of packages affected, whether these transactions succeeded or were aborted, and if the RPM database was changed between transactions. Additionally, this command can be used to undo or redo certain transactions. All history data is stored in the history DB in the
9.4.1. Listing Transactions
To display a list of the twenty most recent transactions, as
root, either run
yum history with no additional arguments, or type the following at a shell prompt:
To display all transactions, add the
To display only transactions in a given range, use the command in the following form:
yum history list start_id..end_id
You can also list only transactions regarding a particular package or packages. To do so, use the command with a package name or a glob expression:
yum history list glob_expression…
Example 9.19. Listing the five oldest transactions
In the output of
yum history list, the most recent transaction is displayed at the top of the list. To display information about the five oldest transactions stored in the history data base, type:
~]# yum history list 1..5 Loaded plugins: langpacks, product-id, subscription-manager ID | Login user | Date and time | Action(s) | Altered ------------------------------------------------------------------------------- 5 | User <user> | 2013-07-29 15:33 | Install | 1 4 | User <user> | 2013-07-21 15:10 | Install | 1 3 | User <user> | 2013-07-16 15:27 | I, U | 73 2 | System <unset> | 2013-07-16 15:19 | Update | 1 1 | System <unset> | 2013-07-16 14:38 | Install | 1106 history list
All forms of the
yum history list command produce tabular output with each row consisting of the following columns:
ID— an integer value that identifies a particular transaction.
Login user— the name of the user whose login session was used to initiate a transaction. This information is typically presented in the
Full Name <username>form. For transactions that were not issued by a user (such as an automatic system update),
System <unset>is used instead.
Date and time— the date and time when a transaction was issued.
Action(s)— a list of actions that were performed during a transaction as described in Table 9.1, “Possible values of the Action(s) field”.
Altered— the number of packages that were affected by a transaction, possibly followed by additional information as described in Table 9.2, “Possible values of the Altered field”.
Table 9.1. Possible values of the Action(s) field
| || || |
At least one package has been downgraded to an older version.
| || || |
At least one package has been removed.
| || || |
At least one new package has been installed.
| || || |
At least one package has been marked as obsolete.
| || || |
At least one package has been reinstalled.
| || || |
At least one package has been updated to a newer version.
Table 9.2. Possible values of the Altered field
| || |
Before the transaction finished, the
| || |
After the transaction finished, the
| || |
The transaction failed to finish.
| || |
The transaction finished successfully, but yum returned a non-zero exit code.
| || |
The transaction finished successfully, but an error or a warning was displayed.
| || |
The transaction finished successfully, but problems already existed in the
| || |
The transaction finished successfully, but the
To synchronize the
yumdb database contents for any installed package with the currently used
yumdb database, type the following:
To display some overall statistics about the currently used history database use the following command:
Example 9.20. Example output of yum history stats
~]# yum history stats Loaded plugins: langpacks, product-id, subscription-manager File : //var/lib/yum/history/history-2012-08-15.sqlite Size : 2,766,848 Transactions: 41 Begin time : Wed Aug 15 16:18:25 2012 End time : Wed Feb 27 14:52:30 2013 Counts : NEVRAC : 2,204 NEVRA : 2,204 NA : 1,759 NEVR : 2,204 rpm DB : 2,204 yum DB : 2,204 history stats
Yum also enables you to display a summary of all past transactions. To do so, run the command in the following form as
To display only transactions in a given range, type:
yum history summary start_id..end_id
Similarly to the
yum history list command, you can also display a summary of transactions regarding a certain package or packages by supplying a package name or a glob expression:
yum history summary glob_expression…
Example 9.21. Summary of the five latest transactions
~]# yum history summary 1..5 Loaded plugins: langpacks, product-id, subscription-manager Login user | Time | Action(s) | Altered ------------------------------------------------------------------------------- Jaromir ... <jhradilek> | Last day | Install | 1 Jaromir ... <jhradilek> | Last week | Install | 1 Jaromir ... <jhradilek> | Last 2 weeks | I, U | 73 System <unset> | Last 2 weeks | I, U | 1107 history summary
All forms of the
yum history summary command produce simplified tabular output similar to the output of
yum history list.
As shown above, both
yum history list and
yum history summary are oriented towards transactions, and although they allow you to display only transactions related to a given package or packages, they lack important details, such as package versions. To list transactions from the perspective of a package, run the following command as
yum history package-list glob_expression…
Example 9.22. Tracing the history of a package
For example, to trace the history of subscription-manager and related packages, type the following at a shell prompt:
~]# yum history package-list subscription-manager\* Loaded plugins: langpacks, product-id, search-disabled-repos, subscription-manager ID | Action(s) | Package ------------------------------------------------------------------------------- 2 | Updated | subscription-manager-1.13.22-1.el7.x86_64 EE 2 | Update | 1.15.9-15.el7.x86_64 EE 2 | Obsoleted | subscription-manager-firstboot-1.13.22-1.el7.x86_64 EE 2 | Updated | subscription-manager-gui-1.13.22-1.el7.x86_64 EE 2 | Update | 1.15.9-15.el7.x86_64 EE 2 | Obsoleting | subscription-manager-initial-setup-addon-1.15.9-15.el7.x86_64 EE 1 | Install | subscription-manager-1.13.22-1.el7.x86_64 1 | Install | subscription-manager-firstboot-1.13.22-1.el7.x86_64 1 | Install | subscription-manager-gui-1.13.22-1.el7.x86_64 history package-list
In this example, three packages were installed during the initial system installation: subscription-manager, subscription-manager-firstboot, and subscription-manager-gui. In the third transaction, all these packages were updated from version 1.10.11 to version 1.10.17.
9.4.2. Examining Transactions
To display the summary of a single transaction, as
root, use the
yum history summary command in the following form:
Here, id stands for the ID of the transaction.
To examine a particular transaction or transactions in more detail, run the following command as
The id argument is optional and when you omit it, yum automatically uses the last transaction. Note that when specifying more than one transaction, you can also use a range:
yum history info start_id..end_id
Example 9.23. Example output of yum history info
The following is sample output for two transactions, each installing one new package:
~]# yum history info 4..5 Loaded plugins: langpacks, product-id, search-disabled-repos, subscription-manager Transaction ID : 4..5 Begin time : Mon Dec 7 16:51:07 2015 Begin rpmdb : 1252:d2b62b7b5768e855723954852fd7e55f641fbad9 End time : 17:18:49 2015 (27 minutes) End rpmdb : 1253:cf8449dc4c53fc0cbc0a4c48e496a6c50f3d43c5 User : Maxim Svistunov <msvistun> Return-Code : Success Command Line : install tigervnc-server.x86_64 Command Line : reinstall tigervnc-server Transaction performed with: Installed rpm-4.11.3-17.el7.x86_64 @rhel-7-server-rpms Installed subscription-manager-1.15.9-15.el7.x86_64 @rhel-7-server-rpms Installed yum-3.4.3-132.el7.noarch @rhel-7-server-rpms Packages Altered: Reinstall tigervnc-server-1.3.1-3.el7.x86_64 @rhel-7-server-rpms history info
You can also view additional information, such as what configuration options were used at the time of the transaction, or from what repository and why were certain packages installed. To determine what additional information is available for a certain transaction, type the following at a shell prompt as
yum history info, when no id is provided, yum automatically uses the latest transaction. Another way to refer to the latest transaction is to use the
Example 9.24. Example output of
For the fourth transaction in the history, the
yum history addon-info command provides the following output:
~]# yum history addon-info 4 Loaded plugins: langpacks, product-id, subscription-manager Transaction ID: 4 Available additional history information: config-main config-repos saved_tx history addon-info
In the output of the
addon-info command, three types of information are available:
config-main— global yum options that were in use during the transaction. See Section 9.5.1, “Setting [main] Options” for information on how to change global options.
config-repos— options for individual yum repositories. See Section 9.5.2, “Setting [repository] Options” for information on how to change options for individual repositories.
saved_tx— the data that can be used by the
yum load-transactioncommand in order to repeat the transaction on another machine (see below).
To display a selected type of additional information, run the following command as
9.4.3. Reverting and Repeating Transactions
Apart from reviewing the transaction history, the
yum history command provides means to revert or repeat a selected transaction. To revert a transaction, type the following at a shell prompt as
To repeat a particular transaction, as
root, run the following command:
Both commands also accept the
last keyword to undo or repeat the latest transaction.
Note that both
yum history undo and
yum history redo commands only revert or repeat the steps that were performed during a transaction. If the transaction installed a new package, the
yum history undo command will uninstall it, and if the transaction uninstalled a package the command will again install it. This command also attempts to downgrade all updated packages to their previous version, if these older packages are still available.
When managing several identical systems, yum also enables you to perform a transaction on one of them, store the transaction details in a file, and after a period of testing, repeat the same transaction on the remaining systems as well. To store the transaction details to a file, type the following at a shell prompt as
yum -q history addon-info id saved_tx >
Once you copy this file to the target system, you can repeat the transaction by using the following command as
yum load-transaction file_name
You can configure
load-transaction to ignore missing packages or rpmdb version. For more information on these configuration options see the
yum.conf(5) man page.
9.4.4. Starting New Transaction History
Yum stores the transaction history in a single SQLite database file. To start new transaction history, run the following command as
This will create a new, empty database file in the
/var/lib/yum/history/ directory. The old transaction history will be kept, but will not be accessible as long as a newer database file is present in the directory.
9.5. Configuring Yum and Yum Repositories
The configuration information for yum and related utilities is located at
/etc/yum.conf. This file contains one mandatory
[main] section, which enables you to set yum options that have global effect, and can also contain one or more
[repository] sections, which allow you to set repository-specific options. However, it is recommended to define individual repositories in new or existing
.repo files in the
/etc/yum.repos.d/ directory. The values you define in individual
[repository] sections of the
/etc/yum.conf file override values set in the
This section shows you how to:
set global yum options by editing the
[main]section of the
set options for individual repositories by editing the
.repofiles in the
use yum variables in
/etc/yum.confand files in the
/etc/yum.repos.d/directory so that dynamic version and architecture values are handled correctly;
- add, enable, and disable yum repositories on the command line; and
- set up your own custom yum repository.
9.5.1. Setting [main] Options
/etc/yum.conf configuration file contains exactly one
[main] section, and while some of the key-value pairs in this section affect how yum operates, others affect how yum treats repositories.
You can add many additional options under the
[main] section heading in
/etc/yum.conf configuration file can look like this:
[main] cachedir=/var/cache/yum/$basearch/$releasever keepcache=0 debuglevel=2 logfile=/var/log/yum.log exactarch=1 obsoletes=1 gpgcheck=1 plugins=1 installonly_limit=3 [comments abridged] # PUT YOUR REPOS HERE OR IN separate files named file.repo # in /etc/yum.repos.d
The following are the most commonly used options in the
assumeyesoption determines whether or not yum prompts for confirmation of critical actions. Replace value with one of:
0(default) — yum prompts for confirmation of critical actions it performs.
1— Do not prompt for confirmation of critical
assumeyes=1is set, yum behaves in the same way as the command-line options
Use this option to set the directory where yum stores its cache and database files. Replace directory with an absolute path to the directory. By default, yum’s cache directory is
See Section 9.5.3, “Using Yum Variables” for descriptions of the
This option specifies the detail of debugging output produced by yum. Here, value is an integer between
10. Setting a higher
debuglevelvalue causes yum to display more detailed debugging output.
debuglevel=2is the default, while
debuglevel=0disables debugging output.
With this option, you can set yum to consider the exact architecture when updating already installed packages. Replace value with:
0— Do not take into account the exact architecture when updating packages.
1(default) — Consider the exact architecture when updating packages. With this setting, yum does not install a package for 32-bit architecture to update a package already installed on the system with 64-bit architecture.
excludeoption enables you to exclude packages by keyword during installation or system update. Listing multiple packages for exclusion can be accomplished by quoting a space-delimited list of packages. Shell glob expressions using wildcards (for example,
?) are allowed.
gpgcheckoption to specify if yum should perform a GPG signature check on packages. Replace value with:
0— Disable GPG signature-checking on packages in all repositories, including local package installation.
1(default) — Enable checking of GPG signature on all packages in all repositories, including local package installation. With
gpgcheckenabled, all packages' signatures are checked.
If this option is set in the
[main]section of the
/etc/yum.conffile, it sets the GPG-checking rule for all repositories. However, you can also set
gpgcheck=valuefor individual repositories instead; that is, you can enable GPG-checking on one repository while disabling it on another. Setting
gpgcheck=valuefor an individual repository in its corresponding
.repofile overrides the default if it is present in
group_commandoption to specify how the
yum group install,
yum group upgrade, and
yum group removecommands handle a package group. Replace value with on of:
simple— Install all members of a package group. Upgrade only previously installed packages, but do not install packages that have been added to the group in the meantime.
compat— Similar to
yum upgradealso installs packages that were added to the group since the previous upgrade.
objects— (default.) With this option, yum keeps track of the previously installed groups and distinguishes between packages installed as a part of the group and packages installed separately. See Example 9.15, “Viewing information on the LibreOffice package group”
Here you can specify which type of packages (optional, default or mandatory) is installed when the
installcommand is called. The default and mandatory package types are chosen by default.
With this option, you can set yum to record transaction history. Replace value with one of:
0— yum should not record history entries for transactions.
1(default) — yum should record history entries for transactions. This operation takes certain amount of disk space, and some extra time in the transactions, but it provides a lot of information about past operations, which can be displayed with the
history_record=1is the default.
For more information on the
historycommand, see Section 9.4, “Working with Transaction History”.Note
Yum uses history records to detect modifications to the
rpmdbdata base that have been done outside of yum. In such case, yum displays a warning and automatically searches for possible problems caused by altering
history_recordturned off, yum is not able to detect these changes and no automatic checks are performed.
installonlypkgs=space separated list of packages
Here you can provide a space-separated list of packages which yum can install, but will never update. See the
yum.conf(5) manual page for the list of packages which are install-only by default.
If you add the
/etc/yum.conf, ensure that you list all of the packages that should be install-only, including any of those listed under the
yum.conf(5). In particular, make sure that kernel packages are always listed in
installonlypkgs(as they are by default), and
installonly_limitis always set to a value greater than
2so that a backup kernel is always available in case the default one fails to boot.
This option sets how many packages listed in the
installonlypkgsdirective can be installed at the same time. Replace value with an integer representing the maximum number of versions that can be installed simultaneously for any single package listed in
The defaults for the
installonlypkgsdirective include several different kernel packages, so be aware that changing the value of
installonly_limitalso affects the maximum number of installed versions of any single kernel package. The default value listed in
installonly_limit=3, and the minimum possible value is
You cannot set
installonly_limit=1because that would make yum remove the running kernel, which is prohibited. If
installonly_limit=1is used, yum fails.
installonly_limit=2ensures that one backup kernel is available. However, it is recommended to keep the default setting
installonly_limit=3, so that you have two backup kernels available.
keepcacheoption determines whether yum keeps the cache of headers and packages after successful installation. Here, value is one of:
0(default) — Do not retain the cache of headers and packages after a successful installation.
1— Retain the cache after a successful installation.
To specify the location for logging output, replace file_name with an absolute path to the file in which yum should write its logging output. By default, yum logs to
- Here value stands for the maximum number of simultaneous connections, default is 5.
multilib_policyoption sets the installation behavior if several architecture versions are available for package install. Here, value stands for:
best— install the best-choice architecture for this system. For example, setting
multilib_policy=beston an AMD64 system causes yum to install the 64-bit versions of all packages.
all— always install every possible architecture for every package. For example, with
allon an AMD64 system, yum would install both the i686 and AMD64 versions of a package, if both were available.
obsoletesoption enables the obsoletes process logic during updates.When one package declares in its spec file that it obsoletes another package, the latter package is replaced by the former package when the former package is installed. Obsoletes are declared, for example, when a package is renamed. Replace value with one of:
0— Disable yum’s obsoletes processing logic when performing updates.
1(default) — Enable yum’s obsoletes processing logic when performing updates.
This is a global switch to enable or disable yum plug-ins, value is one of:
0— Disable all yum plug-ins globally.Important
Disabling all plug-ins is not advised because certain plug-ins provide important yum services. In particular, product-id and subscription-manager plug-ins provide support for the certificate-based
Content Delivery Network(CDN). Disabling plug-ins globally is provided as a convenience option, and is generally only recommended when diagnosing a potential problem with yum.
1(default) — Enable all yum plug-ins globally. With
plugins=1, you can still disable a specific yum plug-in by setting
enabled=0in that plug-in’s configuration file.
For more information about various yum plug-ins, see Section 9.6, “Yum Plug-ins”. For further information on controlling plug-ins, see Section 9.6.1, “Enabling, Configuring, and Disabling Yum Plug-ins”.
Here, directory is an absolute path to the directory where
.repofiles are located. All
.repofiles contain repository information (similar to the
/etc/yum.conf). Yum collects all repository information from
.repofiles and the
[repository]section of the
/etc/yum.conffile to create a master list of repositories to use for transactions. If
reposdiris not set, yum uses the default directory
This option sets the number of times yum should attempt to retrieve a file before returning an error. value is an integer
0or greater. Setting value to
0makes yum retry forever. The default value is
For a complete list of available
[main] options, see the
[main] OPTIONS section of the yum.conf(5) manual page.
9.5.2. Setting [repository] Options
[repository] sections, where repository is a unique repository ID such as
my_personal_repo (spaces are not permitted), allow you to define individual yum repositories. To avoid conflicts, custom repositories should not use names used by Red Hat repositories.
The following is a bare minimum example of the form a
[repository] section takes:
[repository] name=repository_name baseurl=repository_url
[repository] section must contain the following directives:
- Here, repository_name is a human-readable string describing the repository.
Replace repository_url with a URL to the directory where the repodata directory of a repository is located:
If the repository is available over HTTP, use:
If the repository is available over FTP, use:
If the repository is local to the machine, use:
If a specific online repository requires basic HTTP authentication, you can specify your user name and password by prepending it to the URL as
username:password@link. For example, if a repository on http://www.example.com/repo/ requires a user name of "user" and a password of "password", then the
baseurllink could be specified as
Usually this URL is an HTTP link, such as:
Note that yum always expands the
$basearchvariables in URLs. For more information about yum variables, see Section 9.5.3, “Using Yum Variables”.
- If the repository is available over HTTP, use:
[repository] directive are:
This is a simple way to tell yum to use or ignore a particular repository, value is one of:
0— Do not include this repository as a package source when performing updates and installs. This is an easy way of quickly turning repositories on and off, which is useful when you desire a single package from a repository that you do not want to enable for updates or installs.
1— Include this repository as a package source.
Turning repositories on and off can also be performed by passing either the
yum, or through the
Add/Remove Softwarewindow of the PackageKit utility.
Controls parallel downloading of repository packages. Here, value is one of:
auto(default) — parallel downloading is used if possible, which means that yum automatically disables it for repositories created by plug-ins to avoid failures.
on— parallel downloading is enabled for the repository.
off— parallel downloading is disabled for the repository.
[repository] options exist, part of them have the same form and function as certain
[main] options. For a complete list, see the
[repository] OPTIONS section of the yum.conf(5) manual page.
Example 9.25. A sample /etc/yum.repos.d/redhat.repo file
The following is a sample
# # Red Hat Repositories # Managed by (rhsm) subscription-manager # [red-hat-enterprise-linux-scalable-file-system-for-rhel-6-entitlement-rpms] name = Red Hat Enterprise Linux Scalable File System (for RHEL 6 Entitlement) (RPMs) baseurl = https://cdn.redhat.com/content/dist/rhel/entitlement-6/releases/$releasever/$basearch/scalablefilesystem/os enabled = 1 gpgcheck = 1 gpgkey = file:///etc/pki/rpm-gpg/RPM-GPG-KEY-redhat-release sslverify = 1 sslcacert = /etc/rhsm/ca/redhat-uep.pem sslclientkey = /etc/pki/entitlement/key.pem sslclientcert = /etc/pki/entitlement/11300387955690106.pem [red-hat-enterprise-linux-scalable-file-system-for-rhel-6-entitlement-source-rpms] name = Red Hat Enterprise Linux Scalable File System (for RHEL 6 Entitlement) (Source RPMs) baseurl = https://cdn.redhat.com/content/dist/rhel/entitlement-6/releases/$releasever/$basearch/scalablefilesystem/source/SRPMS enabled = 0 gpgcheck = 1 gpgkey = file:///etc/pki/rpm-gpg/RPM-GPG-KEY-redhat-release sslverify = 1 sslcacert = /etc/rhsm/ca/redhat-uep.pem sslclientkey = /etc/pki/entitlement/key.pem sslclientcert = /etc/pki/entitlement/11300387955690106.pem [red-hat-enterprise-linux-scalable-file-system-for-rhel-6-entitlement-debug-rpms] name = Red Hat Enterprise Linux Scalable File System (for RHEL 6 Entitlement) (Debug RPMs) baseurl = https://cdn.redhat.com/content/dist/rhel/entitlement-6/releases/$releasever/$basearch/scalablefilesystem/debug enabled = 0 gpgcheck = 1 gpgkey = file:///etc/pki/rpm-gpg/RPM-GPG-KEY-redhat-release sslverify = 1 sslcacert = /etc/rhsm/ca/redhat-uep.pem sslclientkey = /etc/pki/entitlement/key.pem sslclientcert = /etc/pki/entitlement/11300387955690106.pem
9.5.3. Using Yum Variables
You can use and reference the following built-in variables in
yum commands and in all yum configuration files (that is,
/etc/yum.conf and all
.repo files in the
You can use this variable to reference the release version of Red Hat Enterprise Linux. Yum obtains the value of
distroverpkg=valueline in the
/etc/yum.confconfiguration file. If there is no such line in
/etc/yum.conf, then yum infers the correct value by deriving the version number from the
redhat-releaseproductpackage that provides the
You can use this variable to refer to the system’s CPU architecture as returned when calling Python’s
os.uname()function. Valid values for
You can use
$basearchto reference the base architecture of the system. For example, i686 and i586 machines both have a base architecture of
i386, and AMD64 and Intel 64 machines have a base architecture of
These ten variables are each replaced with the value of any shell environment variables with the same name. If one of these variables is referenced (in
/etc/yum.conffor example) and a shell environment variable with the same name does not exist, then the configuration file variable is not replaced.
To define a custom variable or to override the value of an existing one, create a file with the same name as the variable (without the "
$" sign) in the
/etc/yum/vars/ directory, and add the desired value on its first line.
For example, repository descriptions often include the operating system name. To define a new variable called
$osname, create a new file with "Red Hat Enterprise Linux" on the first line and save it as
~]# echo "Red Hat Enterprise Linux 7" > /etc/yum/vars/osname
Instead of "Red Hat Enterprise Linux 7", you can now use the following in the
9.5.4. Viewing the Current Configuration
To display the current values of global yum options (that is, the options specified in the
[main] section of the
/etc/yum.conf file), execute the
yum-config-manager command with no command-line options:
To list the content of a different configuration section or sections, use the command in the following form:
You can also use a glob expression to display the configuration of all matching sections:
Example 9.26. Viewing configuration of the main section
To list all configuration options and their corresponding values for the main section, type the following at a shell prompt:
~]$ yum-config-manager main \* Loaded plugins: langpacks, product-id, subscription-manager ================================== main =================================== [main] alwaysprompt = True assumeyes = False bandwith = 0 bugtracker_url = https://bugzilla.redhat.com/enter_bug.cgi?product=Red%20Hat%20Enterprise%20Linux%206&component=yum cache = 0 [output truncated]
9.5.5. Adding, Enabling, and Disabling a Yum Repository
To expand your expertise, you might also be interested in the Red Hat System Administration III (RH254) training course.
Section 9.5.2, “Setting [repository] Options” describes various options you can use to define a yum repository. This section explains how to add, enable, and disable a repository by using the
When the system is registered with Red Hat Subscription Management to the certificate-based
Content Delivery Network (CDN), the Red Hat Subscription Manager tools are used to manage repositories in the
Adding a Yum Repository
To define a new repository, you can either add a
[repository] section to the
/etc/yum.conf file, or to a
.repo file in the
/etc/yum.repos.d/ directory. All files with the
.repo file extension in this directory are read by yum, and it is recommended to define your repositories here instead of in
Obtaining and installing software packages from unverified or untrusted software sources other than Red Hat’s certificate-based
Content Delivery Network (CDN) constitutes a potential security risk, and could lead to security, stability, compatibility, and maintainability issues.
Yum repositories commonly provide their own
.repo file. To add such a repository to your system and enable it, run the following command as
yum-config-manager --add-repo repository_url
…where repository_url is a link to the
Example 9.27. Adding example.repo
To add a repository located at http://www.example.com/example.repo, type the following at a shell prompt:
~]# yum-config-manager --add-repo http://www.example.com/example.repo Loaded plugins: langpacks, product-id, subscription-manager adding repo from: http://www.example.com/example.repo grabbing file http://www.example.com/example.repo to /etc/yum.repos.d/example.repo example.repo | 413 B 00:00 repo saved to /etc/yum.repos.d/example.repo
Enabling a Yum Repository
To enable a particular repository or repositories, type the following at a shell prompt as
…where repository is the unique repository ID (use
yum repolist all to list available repository IDs). Alternatively, you can use a glob expression to enable all matching repositories:
yum-config-manager --enable glob_expression…
Example 9.28. Enabling repositories defined in custom sections of /etc/yum.conf.
To enable repositories defined in the
~]# yum-config-manager --enable example\* Loaded plugins: langpacks, product-id, subscription-manager ============================== repo: example ============================== [example] bandwidth = 0 base_persistdir = /var/lib/yum/repos/x86_64/7Server baseurl = http://www.example.com/repo/7Server/x86_64/ cache = 0 cachedir = /var/cache/yum/x86_64/7Server/example [output truncated]
Example 9.29. Enabling all repositories
To enable all repositories defined both in the
/etc/yum.conf file and in the
/etc/yum.repos.d/ directory, type:
~]# yum-config-manager --enable \* Loaded plugins: langpacks, product-id, subscription-manager ============================== repo: example ============================== [example] bandwidth = 0 base_persistdir = /var/lib/yum/repos/x86_64/7Server baseurl = http://www.example.com/repo/7Server/x86_64/ cache = 0 cachedir = /var/cache/yum/x86_64/7Server/example [output truncated]
When successful, the
yum-config-manager --enable command displays the current repository configuration.
Disabling a Yum Repository
To disable a yum repository, run the following command as
…where repository is the unique repository ID (use
yum repolist all to list available repository IDs). Similarly to
yum-config-manager --enable, you can use a glob expression to disable all matching repositories at the same time:
yum-config-manager --disable glob_expression…
Example 9.30. Disabling all repositories
To disable all repositories defined both in the
/etc/yum.conf file and in the
/etc/yum.repos.d/ directory, type:
~]# yum-config-manager --disable \* Loaded plugins: langpacks, product-id, subscription-manager ============================== repo: example ============================== [example] bandwidth = 0 base_persistdir = /var/lib/yum/repos/x86_64/7Server baseurl = http://www.example.com/repo/7Server/x86_64/ cache = 0 cachedir = /var/cache/yum/x86_64/7Server/example [output truncated]
When successful, the
yum-config-manager --disable command displays the current configuration.
9.5.6. Creating a Yum Repository
To set up a yum repository:
Install the createrepo package:
# yum install createrepo
Copy all packages for your new repository into one directory, such as
cp /your/packages/*.rpm /tmp/local_repo/
To create the repository run:
This creates the necessary metadata for the yum repository and places metadata in a newly created subdirectory
The repository is now ready to be consumed by yum. This repository can be shared over the HTTP or FTP protocol, or refered directly from the local machine. See the Section 9.5.2, “Setting [repository] Options” section for more details on how to configure a yum repository.Note
When constructing the URL for a repository, refer to the
/mnt/local_repo/repodata, as this directory contains only metadata. Actual yum packages are in
22.214.171.124. Adding packages to an already created yum repository
To add packages to an already created yum repository:
Copy the new packages to your repository directory, such as
cp /your/packages/*.rpm /tmp/local_repo/
To reflect the newly added packages in the metadata, run:
createrepo --update /tmp/local_repo/
Optional: If you have already used any yum command with newly updated repository, run:
yum clean expire-cache
9.5.7. Adding the Optional and Supplementary Repositories
The Optional and Supplementary subscription channels provide additional software packages for Red Hat Enterprise Linux that cover open source licensed software (in the Optional channel) and proprietary licensed software (in the Supplementary channel).
Before subscribing to the Optional and Supplementary channels see the Scope of Coverage Details. If you decide to install packages from these channels, follow the steps documented in the article called How to access Optional and Supplementary channels, and -devel packages using Red Hat Subscription Manager (RHSM)? on the Red Hat Customer Portal.
9.6. Yum Plug-ins
Yum provides plug-ins that extend and enhance its operations. Certain plug-ins are installed by default. Yum always informs you which plug-ins, if any, are loaded and active whenever you call any
yum command. For example:
~]# yum info yum Loaded plugins: langpacks, product-id, subscription-manager [output truncated]
Note that the plug-in names which follow
Loaded plugins are the names you can provide to the
9.6.1. Enabling, Configuring, and Disabling Yum Plug-ins
To enable yum plug-ins, ensure that a line beginning with
plugins= is present in the
[main] section of
/etc/yum.conf, and that its value is
You can disable all plug-ins by changing this line to
Disabling all plug-ins is not advised because certain plug-ins provide important yum services. In particular, the product-id and subscription-manager plug-ins provide support for the certificate-based
Content Delivery Network (CDN). Disabling plug-ins globally is provided as a convenience option, and is generally only recommended when diagnosing a potential problem with yum.
Every installed plug-in has its own configuration file in the
/etc/yum/pluginconf.d/ directory. You can set plug-in specific options in these files. For example, here is the aliases plug-in’s
aliases.conf configuration file:
Similar to the
/etc/yum.conf file, the plug-in configuration files always contain a
[main] section where the
enabled= option controls whether the plug-in is enabled when you run
yum commands. If this option is missing, you can add it manually to the file.
If you disable all plug-ins by setting
/etc/yum.conf, then all plug-ins are disabled regardless of whether they are enabled in their individual configuration files.
If you merely want to disable all yum plug-ins for a single
yum command, use the
If you want to disable one or more yum plug-ins for a single
yum command, add the
--disableplugin=plugin_name option to the command. For example, to disable the aliases plug-in while updating a system, type:
~]# yum update --disableplugin=aliases
The plug-in names you provide to the
--disableplugin= option are the same names listed after the
Loaded plugins line in the output of any
yum command. You can disable multiple plug-ins by separating their names with commas. In addition, you can match multiple plug-in names or shorten long ones by using glob expressions:
~]# yum update --disableplugin=aliases,lang*
9.6.2. Installing Additional Yum Plug-ins
Yum plug-ins usually adhere to the
yum-plugin-plugin_name package-naming convention, but not always: the package which provides the kabi plug-in is named
kabi-yum-plugins, for example. You can install a yum plug-in in the same way you install other packages. For instance, to install the yum-aliases plug-in, type the following at a shell prompt:
~]# yum install yum-plugin-aliases
9.6.3. Working with Yum Plug-ins
The following list provides descriptions and usage instructions for several useful yum plug-ins. Plug-ins are listed by names, brackets contain the name of the package.
- search-disabled-repos (subscription-manager)
The search-disabled-repos plug-in allows you to temporarily or permanently enable disabled repositories to help resolve dependencies. With this plug-in enabled, when Yum fails to install a package due to failed dependency resolution, it offers to temporarily enable disabled repositories and try again. If the installation succeeds, Yum also offers to enable the used repositories permanently. Note that the plug-in works only with the repositories that are managed by subscription-manager and not with custom repositories.Important
yumis executed with the
-yoption, or if the
assumeyesdirective is enabled in
/etc/yum.conf, the plug-in enables disabled repositories, both temporarily and permanently, without prompting for confirmation. This may lead to problems, for example, enabling repositories that you do not want enabled.
To configure the search-disabled-repos plug-in, edit the configuration file located in
/etc/yum/pluginconf.d/search-disabled-repos.conf. For the list of directives you can use in the
[main]section, see the table below.
Table 9.3. Supported
Allows you to enable or disable the plug-in. The value must be either
0(disabled). The plug-in is enabled by default.
Allows you to restrict the behavior of the plug-in to notifications only. The value must be either
1(notify only without modifying the behavior of Yum), or
0(modify the behavior of Yum). By default the plug-in only notifies the user.
Allows you to specify the repositories that will not be enabled by the plug-in.
- kabi (kabi-yum-plugins)
The kabi plug-in checks whether a driver update package conforms with the official Red Hat kernel Application Binary Interface (kABI). With this plug-in enabled, when a user attempts to install a package that uses kernel symbols which are not on a whitelist, a warning message is written to the system log. Additionally, configuring the plug-in to run in enforcing mode prevents such packages from being installed at all.
To configure the kabi plug-in, edit the configuration file located in
/etc/yum/pluginconf.d/kabi.conf. A list of directives that can be used in the
[main]section is shown in the table below.
Table 9.4. Supported
Allows you to enable or disable the plug-in. The value must be either
0(disabled). When installed, the plug-in is enabled by default.
Allows you to specify the directory in which the files with supported kernel symbols are located. By default, the kabi plug-in uses files provided by the kernel-abi-whitelists package (that is, the
Allows you to enable or disable enforcing mode. The value must be either
0(disabled). By default, this option is commented out and the kabi plug-in only displays a warning message.
- product-id (subscription-manager)
- The product-id plug-in manages product identity certificates for products installed from the Content Delivery Network. The product-id plug-in is installed by default.
- langpacks (yum-langpacks)
- The langpacks plug-in is used to search for locale packages of a selected language for every package that is installed. The langpacks plug-in is installed by default.
- aliases (yum-plugin-aliases)
The aliases plug-in adds the
aliascommand-line option which enables configuring and using aliases for
- yum-changelog (yum-plugin-changelog)
The yum-changelog plug-in adds the
--changelogcommand-line option that enables viewing package change logs before and after updating.
- yum-tmprepo (yum-plugin-tmprepo)
The yum-tmprepo plug-in adds the
--tmprepocommand-line option that takes the URL of a repository file, downloads and enables it for only one transaction. This plug-in tries to ensure the safe temporary usage of repositories. By default, it does not allow to disable the gpg check.
- yum-verify (yum-plugin-verify)
The yum-verify plug-in adds the
verify-allcommand-line options for viewing verification data on the system.
- yum-versionlock (yum-plugin-versionlock)
The yum-versionlock plug-in excludes other versions of selected packages, which enables protecting packages from being updated by newer versions. With the
versionlockcommand-line option, you can view and edit the list of locked packages.
9.7. Automatically Refreshing Package Database and Downloading Updates with Yum-cron
yum-cron service checks and downloads package updates automatically. The cron jobs provided by the
yum-cron service are active immediately after installation of the yum-cron package. The
yum-cron service can also automatically install downloaded updates.
With default settings, the
- Updates the metadata in the yum cache once per hour.
- Downloads pending package updates to the yum cache once per day. If new packages are available in the repository, an email is sent. See chapter Section 9.7.2, “Setting up Optional Email Notifications” for more information.
yum-cron service has two configuration files:
- For daily tasks.
- For hourly tasks.
9.7.1. Enabling Automatic Installation of Updates
To enable automatic installation of downloaded updates, edit the daily configuration file for daily installation or the hourly configuration file for hourly installation by setting the
apply_updates option as follows:
apply_updates = yes
9.7.2. Setting up Optional Email Notifications
By default, the
yum-cron service uses
cron to send emails containing an output of the executed command. This email is sent according to
cron configuration, typically to the local superuser and stored in the
You can use specific email configuration different from the settings which affect all
cron jobs. However, this email configuration does not support TLS and overall email built-in logic is very basic.
yum-cron built-in email notifications:
- For daily tasks.
- For hourly tasks.
[emitters]section, set the following option:
emit_via = email
email_hostoptions as required
9.7.3. Enabling or Disabling Specific Repositories
yum-cron does not support specific configuration of repositories. As a workaround for enabling or disabling specific repositories for
yum-cron but not for
yum in general follow the steps bellow:
- Create an empty repository configuration directory anywhere on the system.
Copy all configuration files from the
/etc/yum.repos.d/directory to this newly created directory.
In the respective
.repoconfiguration file within the
/etc/yum.repos.d/, set the
enabledoption as follows:
enabled = 1
- To enable the repository.
enabled = 0
- To disable the repository.
Add the following option, which points to the newly created repository directory, at the end of the selected
9.7.4. Testing Yum-cron Settings
yum-cron settings without waiting for the next scheduled
- For daily tasks.
- For hourly tasks.
random_sleepoption in the selected configuration file as follows:
random_sleep = 0
Run the configuration files:
# yum-cron /etc/yum/yum-cron.conf # yum-cron /etc/yum/yum-cron-hourly.conf
9.7.5. Disabling Yum-cron messages
yum-cron messages cannot be entirely disabled, but can be limited to messages with critical priority only. To limit the messages:
- For daily tasks.
- For hourly tasks.
Set the following option in the
[base]section of the configuration file:
debuglevel = -4
9.7.6. Automatically Cleaning Packages
yum-cron service does not support any configuration option for removing packages similar to the
yum clean all command. To clean packages automatically, you can create a cron job as an executable shell script:
Create a shell script in the
#!/bin/sh yum clean all
Make the script executable:
# chmod +x /etc/cron.daily/script-name.sh
9.8. Additional Resources
For more information on how to manage software packages on Red Hat Enterprise Linux, see the resources listed below.
yum(8) — The manual page for the yum command-line utility provides a complete list of supported options and commands.
yumdb(8) — The manual page for the
yumdbcommand-line utility documents how to use this tool to query and, if necessary, alter the yum database.
yum.conf(5) — The manual page named
yum.confdocuments available yum configuration options.
yum-utils(1) — The manual page named
yum-utilslists and briefly describes additional utilities for managing yum configuration, manipulating repositories, and working with yum database.
Chapter 6, Gaining Privileges documents how to gain administrative privileges by using the