Running Linux, 5th Edition - Matthias Kalle Dalheimer [226]
Figure 12-3. SUSE Watcher indicates available security patches
Red Carpet and ZENworks Linux Management: Alternative Package Management Tools
This section looks at another tool for automated update management, called Red Carpet (now part of the ZENworks Linux Management tools from Novell), and explains some of the advantages of different approaches to package management.
Originally developed as an updater for GNOME desktop software, Red Carpet is currently distributed by Novell as part of SUSE Linux distributions and is also available from other sources as a standalone system updater. It can install updates from a variety of servers, including apt repositories and ZENworks servers. Administrators of several flavors of Linux will appreciate having the Red Carpet tools on all their systems, because they provide a consistent interface and command set that abstracts away the package management quirks of individual distributions.
The client side of the package system consists of a daemon (rcd, soon to be changed to zmd), a command-line interface (rug), and a graphical interface. All three of these pieces are free software, although Novell sells a proprietary server application as part of its overall software management suite. The server side is designed for very large, complex organizations and won't be covered here, but we will cover a free alternative for software distribution, Open Carpet.
The ZENworks system distributes Linux software divided into channels, like television shows. Each channel contains a group of individual RPM packages that are related in some way: core operating system, for example, or games. Each package is also assigned a section, such as Productivity or Multimedia, to help you find applications that perform a particular task. You can subscribe to channels the way you would with cable television, so that they can show only software you are interested in. This is particularly useful when there are multiple channels offering different versions of the same application, such as one for the stable branch of Evolution, and one for unstable developer snapshots.
Red Carpet, like other tools, will handle all dependency checking for you: if you try to install a new version of Evolution, and it requires that you upgrade gtkhtml, the program will offer to upgrade that as well. Similarly, if you try to remove software that is required, Red Carpet will warn you that, to keep a clean package database, it will be removing everything upstream from that. For example, if you try to remove the gtk+ package, you'll also have to tear out most of your GNOME desktop tools, which almost universally require that library.
Installing Red Carpet
You can download Red Carpet RPM packages from ftp://ftp.novell.com or from your Linux distribution's web site. You may also wish to check http://rpmfind.net or http://open-carpet.org for additional sources. You will need the daemon package rcd or zmd and at least one of the rug (command-line) or Red Carpet (GUI) interface tools. The packages have few dependencies, so you should be able to install them no trouble using the command rpm -Uvh.
Using the Red Carpet GUI
The Red Carpet graphical update tool can be invoked either from a menu or with the red-carpet command. When you first start it, it will tell you that there are no updates available, because you have not subscribed to any channels. To change your channel subscriptions, click the Channels button and select the items you want.
Once you have subscribed to channels, the start screen of Red Carpet will display new versions of packages you already have installed, if any are available. Each update is displayed with its name, the version you have and the version of the updated package, plus a recommendation as to how important that update is, ranging from "minor" for small enhancements to "urgent"