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urpmihowto

NAME

urpmihowto - urpmi Advanced How-To

Basic notions

Packages and media

The urpmi suite of tools has for main purpose to download and to install RPM packages easily.

Software packages often depend on each other; urpmi is able to recognize those dependencies, to download missing required packages as needed, and to remove conflicting packages if it needs to.

urpmi gets the list of available RPMs, and the RPMs themselves, from a media. Roughly speaking, a media is described by a name and by a location, specified by an URL. Currently supported media types are: local drives, removable drives (such as CDs), ISO images, and networked media via different protocols (http, ftp, ssh and rsync). NFS mounted directories are treated like local drives.

Installing and updating RPMs

The tool used to install RPMs is urpmi. Its basic usage is as follows:

     urpmi <list of package names>
 
 

That prompts urpmi to fetch and install all packages and their unmet dependencies from the media you have configured. In the process, urpmi might ask a few questions. Notably, if some packages need to be upgraded, or if some new (unspecified) packages should be installed, it will ask for confirmation. If some packages need to be removed (due to conflicts with the requested packages), urpmi will ask for confirmation as well. In some cases, urpmi will also propose a choice between different alternatives, usually proposing the ``best'' package as a default.

Another very useful mode of action for urpmi is to ask it to upgrade all packages to the latest version found on the media. This is done by

     urpmi --auto-update
 
 

urpmi can also help installing RPM files directly. Instead of using "rpm -i foobar.rpm", you can pass the path to the rpm file to urpmi: it will then try to resolve the needed dependencies.

Useful options to urpmi include :

--auto

automatic mode: urpmi will not ask questions and always select the default choice.

--test

tests the installation of packages, but do not actually install anything or modify the system.

--media media1,...,mediaN

Use only the specified media, instead of defaulting to all available media. You can also specify a substring of media names, and urpmi will select all media that contain this substring. (For example,

     urpmi --auto-update --media updates
 
 

will search updates from all media that have ``updates'' in their name.)

See the urpmi(8) manpage for the complete reference of all options that urpmi supports.

Removing RPMs

The tool used to deinstall RPMs is urpme. The command

     urpme <list of package names>
 
 

will attempt to remove all listed packages, plus the packages that depend on them. It will refuse to uninstall ``important'' packages (that is, the ones that are part of the base system.)

See the urpme(8) manpage for the reference of all options urpme supports.

urpme isn't able to detect packages that are no longer used: for example, libraries that no application requires. To clean them up, a handy tool is rpm-find-leaves. It will list all RPMs on your system that no other package requires.

Media management

Adding media

urpmi is usable only when you have defined some media. Usually the OS installation procedure configures a predefined set of media, which correspond to the installation method you've selected: that might be installation CDs, or an HTTP or FTP server if you installed from a networked mirror, and so on. But you might want to add media yourself. For that, you should use the urpmi.addmedia program. Its usage is as follows:

     urpmi.addmedia [options] <name> <url>
 
 

In this synopsis, "<name>" is the name of the new media, "<url>" the URL where the RPMs are to be found.

Supported URLs can be "http://", "ftp://", "rsync://", "ssh://" (this will use rsync over ssh), "file://", and "removable://" ("removable://" works like "file://", but instructs urpmi that the directory is mounted from a removable media, such as a CD or a DVD.) If the media requires authentication, you can use the usual URL syntax:

     <scheme>://<login>:<pass>@host/path
 
 

Those credentials won't be stored in any world-readable file.

In some cases, if your media points at an external HTTP or FTP server, you might want to use a proxy to access it. This is possible by using the "--proxy" and "--proxy-user" options (the second one in case of your proxy requires authentication.)

Removing media

This is straightforward; to remove a media "foo", simply use the command:

     urpmi.removemedia foo
 
 

Updating media

Some media never change; this is the case, for example, for CD-ROMs and the like. However, some other ones --- typically updates --- grow; new RPMs are added to them, and old ones are removed. Thus, before using them, from time to time, you should instruct urpmi that their contents might have changed.

To do this, use the urpmi.update program. You can either update all media:

     urpmi.update -a
 
 

or update only media specifically named:

     urpmi.update updates-one updates-two
 
 

Creating your own media

The easiest way to create your own media is to let urpmi.addmedia do it. However, this will work well only if you have a small number of rpms, stored on disk or on a shared NFS mount. To do that, assuming that your RPMs are under a directory /var/my-rpms, simply enter the command:

     urpmi.addmedia my-media /var/my-rpms
 
 

However, to create media containing a large number of RPMs, or to be put on a shared server, you'll need to use the gendistrib tool. It comes in the "rpmtools" package. It is able to generate a mirror tree for one or several media.

A typical media repository, under a root directory /ROOT/, has the following structure: (here, we have two media, named "first" and "second")

     ROOT/ - media/
             |- first/
             |   `- media_info/
             |- second/
             |   `- media_info/
             `- media_info/
 
 

The RPMs are place in the "first" and "second" subdirectories. Repository metadata is contained in the top-level media_info directory. Per-media metadata are contained in the first/media_info and second/media_info subdirectories.

Per-media metadata consists in an "hdlist.cz" file, that contains the gzipped headers of the RPMs in the media, a "synthesis.hdlist.cz" file, much smaller than the hdlist and that contains only the information necessary to urpmi to resolve dependencies, and optionnally a "pubkey" file if the RPMs are signed (so urpmi can check that the RPMs it downloads are signed with the key associated to this media.)

Before using gendistrib, you must create a file media_info/media.cfg to describe this media repository. The syntax of this file is reminiscent of .ini files. It contains one section per media: for example,

     [first]
     hdlist=hdlist_first.cz
     name=First supplementary media
 
 

Here, "first" is the directory name, "hdlist_first.cz" is the name of the hdlist file that will be created (it must end with ".cz"), and "name=" gives a human-readable descriptive name for the media.

Then, you can run gendistrib. It should be passed the /ROOT/ directory as parameter. It will then generate the hdlist and synthesis files and all other files needed for proper repository operation.

For further information, see the gendistrib(1) manpage.

Searching for packages

urpmf

urpmf is a grep-like tool for the urpmi database (the database of all RPMs in the media). By default, it will search through the file names contained in packages, but a variety of options allows to search through package names, provides, requires, RPM descriptions, etc. (or several of those at once.)

For example, to find all packages that begin with ``apache-'' :

     urpmf --name '^apache-'
 
 

(the ^ being the beginning-of-line anchor used in standard regular expressions.)

To find all packages that contain files whose pathname includes /etc/httpd.conf.d :

     urpmf /etc/httpd.conf.d
 
 

To find all packages that provide ``mail-server'', with their version and release number (-f) :

     urpmf --provides -f mail-server
 
 

See the urpmf(8) manpage for more examples and the list of all options.

urpmq

urpmq is a tool to query the urpmi database. It has several modes of operation. Here are a couple of useful uses.

     urpmq -i package
 
 

will list the information for that package (like "rpm -qi" would do for installed packages.) The "--summary" option is similar, but gives only one-line concise information.

     urpmq --source package
 
 

will give the URL from which the package can be retrieved.

     urpmq -d package
 
 

will give the list of all RPMs that are required by the specified package (recursively).

Inversely, the command

     urpmq -R package
 
 

will give the list of all RPMs that require the specified package.

See the urpmq(8) manpage for the list of all options.

urpmi-parallel

urpmi-parallel is an add-on to urpmi that is useful to install packages on a network: it will run an urpmi command in parallel on a specified number of hosts. In more detail, the machine you run the command on (the ``server'') tests its result on each machine in the group in turn (the ``clients''), downloads all necessary packages for all machines in the group, distributes the appropriate packages to each machine, then calls urpmi on the machine to do the actual installation.

urpmi must be installed on all client machines, but it is not necessary to have media defined on these.

To use it, follow those steps :

•

make sure you can ssh from the server to each client machine as root (you can use ssh-add on the server host to avoid entering your passphrase and/or password many times).

•

install urpmi-parallel-ssh and/or urpmi-parallel-ka-run on the server machine. The first plugin uses plain ssh to distribute commands to other hosts, the second one uses ka-run, an efficient parallelization method on top of any remote shell (rsh or ssh), adapted to clusters.

•

Edit /etc/urpmi/parallel.cfg to look something like this:

     mynetwork:ssh:host1:host2:host3
 
 

On this line, "mynetwork" is the name of the alias you'll use to specify the network to urpmi, "ssh" is the install method (to use "ka-run", look up the entry for /etc/urpmi/parallel.cfg in urpmi.files(5)), and hostN are the hostnames of all clients on your network. You can put "localhost" in this list.

•

Run the urpmi command : for example, to install ``package_name'' :

     urpmi --parallel mynetwork package_name
 
 

urpmi.recover

urpmi.recover is a tool to help management of RPM rollbacks. One rarely used feature of RPM is that it can ``repackage'' the RPMs it deinstalls (either because they are upgraded to a newer version, or because they are plainly erased), and then reinstall the repackaged RPMs, thereby restoring the system to a previous (hopefully more stable) state.

urpmi.recover has three main functions:

define a checkpoint

"urpmi.recover --checkpoint" is used to define a point in your system that you consider stable, and to start storing info that will enable you to rollback to this state (or to any later state).

list installations you've done

"urpmi.recover --list date" is used to list chronologically all installations and upgrades on your system up to the specified date. The output format gives them grouped by installation transactions. (This option has two variants, "--list-all" and "--list-safe".) Here are some examples :

List all installations made during the last day :

     urpmi.recover --list '1 day ago'
 
 

List all installations since 7th february 2006 :

     urpmi.recover --list 2006-02-07
 
 

List all installations since the checkpoint :

     urpmi.recover --list-safe
 
 

Lists all installations and upgrades known to the RPM database :

     urpmi.recover --list-all
 
 

perform rollbacks

"urpmi.recover --rollback" is used to roll back installations and upgrades to a previous point in the past (at most until your checkpoint.) It has two variants :

To roll back until a specified date :

     urpmi.recover --rollback <date>
 
 

The date can be a duration (for example ``2 hours ago'') or a date given in YYYY-MM-SS hh:mm format.

To roll back a specified number of transactions :

     urpmi.recover --rollback <number of transactions>
 
 

In both cases, be careful not to rollback beyond the checkpoint!

Once you've defined a checkpoint, when you use urpmi, urpme or directly rpm to install or remove packages, the older packages will be stored in /var/spool/repackage. You thus must make sure you have enough space on this partition to store all repackaged RPMs.

Technically, defining a checkpoint is equivalent to writing a file /etc/rpm/macros.d/urpmi.recover.macros that overrides the rpm macros used to set up the repackaging functionalities of rpm. You can change %_repackage_dir there if you want to, if you don't want to store repackaged RPMs in /var/spool/repackage.

If you want to disable the repackaging functionality and clean up the repackage spool, use "urpmi.recover --disable". Warning: rollbacks won't be possible anymore.

Restricted urpmi

urpmi has a ``restricted'' counterpart: rurpmi. It is similar to urpmi, but has a stripped-down set of features. It's intended to be used by users without root privileges, but with sudo rights on it, preventing any abuse of this tool to compromise the system.

Its syntax is similar to the one of urpmi, but it disallows installing arbitrary RPMs: those are forcibly downloaded from a registered media. A number of dangerous options, listed in the rurpmi(8) manpage, are also forbidden.