Using RPM
RPM has five basic modes of operation (not
counting package building): installing, uninstalling, upgrading,
querying, and verifying. This section contains an overview of each
mode. For complete details and options try rpm
--help, or turn to the Section called Additional Resources for more information on
RPM.
Finding RPM Packages
Before using an RPM, you must know where to
find them. An Internet search will return many
RPM repositories, but if you are looking
for RPM packages built by Red Hat, they can
be found at the following locations:
The official Red Hat Linux CD-ROMs
The Red Hat Errata Page available at http://www.redhat.com/apps/support/errata/
A Red Hat FTP Mirror Site available at http://www.redhat.com/download/mirror.html
Red Hat Network — See Chapter 33 for more
details on Red Hat Network
Installing
RPM packages typically have file names like
foo-1.0-1.i386.rpm. The file name includes the
package name (foo), version
(1.0), release (1), and
architecture (i386). Installing a package is as
simple as logging in as root and typing the following command at a
shell prompt:
rpm -Uvh foo-1.0-1.i386.rpm |
If installation is successful, you will see the following:
Preparing... ########################################### [100%]
1:foo ########################################### [100%] |
As you can see, RPM prints out the name of the package and then prints
a succession of hash marks as the package is installed as a progress
meter.
Starting with version 4.1 of RPM, the signature of a package is
checked when installing or upgrading a package. If verifying the
signature fails, you will see an error message such as:
error: V3 DSA signature: BAD, key ID 0352860f |
If is it a new, header-only, signature, you will see an error message
such as:
error: Header V3 DSA signature: BAD, key ID 0352860f |
If you do not have the appropriate key installed to verify the
signature, the message will contain
NOKEY such as:
warning: V3 DSA signature: NOKEY, key ID 0352860f |
Refer to the Section called Checking a Package's Signature for more information on
checking a package's signature.
 | Note |
|---|
| | If you are installing a kernel package, you should use rpm
-ivh instead. Refer to Chapter 29 for details.
|
Installing packages is designed to be simple, but you may sometimes
see errors.
Package Already Installed
If the package of the same version is already installed, you will see:
Preparing... ########################################### [100%]
package foo-1.0-1 is already installed |
If you want to install the package anyway and the same version you
are trying to install is already installed, you can use the
--replacepkgs option, which tells
RPM to ignore the error:
rpm -ivh --replacepkgs foo-1.0-1.i386.rpm |
This option is helpful if files installed from the RPM were deleted
or if you want the original configuration files from the RPM to be
installed.
Conflicting Files
If you attempt to install a package that contains a file which has
already been installed by another package or an earlier version of
the same package, you will see:
Preparing... ########################################### [100%]
file /usr/bin/foo from install of foo-1.0-1 conflicts with file from package bar-2.0.20 |
To make RPM ignore this error, use the
--replacefiles option:
rpm -ivh --replacefiles foo-1.0-1.i386.rpm |
Unresolved Dependency
RPM packages can "depend" on other
packages, which means that they require other packages to be
installed in order to run properly. If you try to install a package
which has an unresolved dependency, you will see:
Preparing... ########################################### [100%]
error: Failed dependencies:
bar.so.2 is needed by foo-1.0-1
Suggested resolutions:
bar-2.0.20-3.i386.rpm |
If you are installing an official Red Hat, it will usually suggest the
package(s) need to resolve the dependency. Find this package on the
Red Hat Linux CD-ROMs or from the Red Hat FTP site (or mirror), and add it to
the command:
rpm -ivh foo-1.0-1.i386.rpm bar-2.0.20-3.i386.rpm |
If installation of both packages is successful, you will see:
Preparing... ########################################### [100%]
1:foo ########################################### [ 50%]
2:bar ########################################### [100%] |
If it does not suggest a package to resolve the dependency, you can
try the --redhatprovides option to determine
which package contains the required file. You need the
rpmdb-redhat package installed to use this
options.
rpm -q --redhatprovides bar.so.2 |
If the package that contains bar.so.2 is in the
installed database from the rpmdb-redhat
package, the name of the package will be displayed:
If you want to force the installation anyway (a bad idea since the
package probably will not run correctly), use the
--nodeps option.
Uninstalling
Uninstalling a package is just as simple as installing one. Type the
following command at a shell prompt:
| Note |
|---|
| | Notice that we used the package name
foo, not the name of the original package
file
foo-1.0-1.i386.rpm. To uninstall a package, you
will need to replace foo with the actual
package name of the original package.
|
You can encounter a dependency error when uninstalling a package if
another installed package depends on the one you are trying to remove.
For example:
Preparing... ########################################### [100%]
error: removing these packages would break dependencies:
foo is needed by bar-2.0.20-3.i386.rpm |
To cause RPM to ignore this error and uninstall the package anyway
(which is also a bad idea since the package that depends on it will
probably fail to work properly), use the --nodeps
option.
Upgrading
Upgrading a package is similar to installing one. Type the following
command at a shell prompt:
rpm -Uvh foo-2.0-1.i386.rpm |
What you do not see above is that RPM
automatically uninstalled any old versions of the
foo package. In fact, you may want to always use
-U to install packages, since it will work even
when there are no previous versions of the package installed.
Since RPM performs intelligent upgrading of
packages with configuration files, you may see a message like the
following:
saving /etc/foo.conf as /etc/foo.conf.rpmsave |
This message means that your changes to the configuration file may not
be "forward compatible" with the new configuration file in the
package, so RPM saved your original file,
and installed a new one. You should investigate the differences
between the two configuration files and resolve them as soon as
possible, to ensure that your system continues to function properly.
Upgrading is really a combination of uninstalling and installing, so
during an RPM upgrade you can encounter
uninstalling and installing errors, plus one more. If
RPM thinks you are trying to upgrade to a
package with an older version number, you will
see:
package foo-2.0-1 (which is newer than foo-1.0-1) is already installed |
To cause RPM to "upgrade" anyway, use the
--oldpackage option:
rpm -Uvh --oldpackage foo-1.0-1.i386.rpm |
Freshening
Freshening a package is similar to upgrading one. Type the following
command at a shell prompt:
rpm -Fvh foo-1.2-1.i386.rpm |
RPM's freshen option checks the versions of
the packages specified on the command line against the versions of
packages that have already been installed on your system. When a
newer version of an already-installed package is processed by
RPM's freshen option, it will be upgraded
to the newer version. However, RPM's
freshen option will not install a package if no previously-installed
package of the same name exists. This differs from
RPM's upgrade option, as an upgrade
will install packages, whether or not an older
version of the package was already installed.
RPM's freshen option works for single
packages or a group of packages. If you have just downloaded a large
number of different packages, and you only want to upgrade those
packages that are already installed on your system, freshening will do
the job. If you use freshening, you will not have to delete any
unwanted packages from the group that you downloaded before using RPM.
In this case, you can simply issue the following command:
RPM will automatically upgrade only those
packages that are already installed.
Querying
Use the rpm -q command to query the database of
installed packages. The rpm -q foo command will
print the package name, version, and release number of the installed
package foo:
| Note |
|---|
| | Notice that we used the package name
foo. To query a package, you will need to
replace foo with the actual package name.
|
Instead of specifying the package name, you can use the following
options with -q to specify the package(s) you want
to query. These are called Package Specification
Options.
-a queries all currently installed packages.
-f <file>
will query the package which owns
<file>.
When specifying a file, you must specify the full path of the file
(for example, /usr/bin/ls).
-p <packagefile>
queries the package
<packagefile>.
There are a number of ways to specify what information to display
about queried packages. The following options are used to select the
type of information for which you are searching. These are called
Information Selection Options.
-i displays package information including name,
description, release, size, build date, install date, vendor, and
other miscellaneous information.
-l displays the list of files that the package
contains.
-s displays the state of all the files in the
package.
-d displays a list of files marked as
documentation (man pages, info pages, READMEs, etc.).
-c displays a list of files marked as
configuration files. These are the files you change after
installation to adapt the package to your system (for example,
sendmail.cf, passwd,
inittab, etc.).
For the options that display lists of files, you can add
-v to the command to display the lists in a
familiar ls -l format.
Verifying
Verifying a package compares information about files installed from a
package with the same information from the original package. Among
other things, verifying compares the size, MD5 sum, permissions, type,
owner, and group of each file.
The command rpm -V verifies a package. You can use
any of the Package Selection Options listed for
querying to specify the packages you wish to verify. A simple use of
verifying is rpm -V foo, which verifies that all
the files in the foo package are as they were when they were
originally installed. For example:
To verify a package containing a particular file:
To verify ALL installed packages:
To verify an installed package against an
RPM package file:
rpm -Vp foo-1.0-1.i386.rpm |
This command can be useful if you suspect that your
RPM databases are corrupt.
If everything verified properly, there will be no output. If there
are any discrepancies they will be displayed. The format of the
output is a string of eight characters (a
c denotes a configuration file) and
then the file name. Each of the eight characters denotes the result
of a comparison of one attribute of the file to the value of that
attribute recorded in the RPM database. A
single . (a period) means the test
passed. The following characters denote failure of certain tests:
If you see any output, use your best judgment to determine if you
should remove or reinstall the package, or fix the problem in another
way.
