SuSE provides a pair of system configuration tools, YaST and YaST2. The former is text-mode, and the latter is GUI; however, they're quite similar in capabilities. I refer to them collectively as YaST for simplicity's sake. Navigating YaST is much like navigating Mandrake's Control Center; you select configuration tools from a hierarchical list. In YaST2 (as shown in Figure 9.5), tool categories appear in the pane on the left of the window, and individual tools are on the right.

Figure 9.5: YaST and YaST2 tools provide convenient access to many configuration options.

A few of SuSE's features are a bit odd compared to most other Linux distributions, but they are not nearly as unusual as Slackware's files. You must be familiar with these oddities in order to modify configurations manually. Important scripts and configuration files include:

System Startup Procedure SuSE's /etc/inittab calls /etc/init.d/boot as the system initialization script. This script calls the startup scripts in /etc/init.d/boot.d and the /etc/init.d/boot.local file (the latter is intended for local startup scripts—those created by the system administrator). SuSE's init then switches to the runlevel specified in /etc/inittab and runs the startup scripts in the appropriate SysV startup script directory.

Location of SysV Startup Scripts SuSE places its SysV startup scripts in /etc/init.d and places links to these files for specific runlevels in /etc/init.d/rc?.d, where ? is the runlevel number.

Runlevels and Starting X Runlevel 3 produces a text-mode login prompt. Runlevel 5 starts an XDMCP server, and therefore X, at boot time. SuSE does this by providing a start link to /etc/init.d/xdm in the /etc/init.d/rc5.d directory. The xdm startup script in turn uses /etc/sysconfig/displaymanager to set several variables, including

DISPLAYMANAGER, which tells the system which XDMCP server to run.

cron SuSE's default cron configuration includes an /etc/crontab file that calls files in the /etc/cron.interval directories, where interval is hourly, daily, weekly, or monthly. Except for the hourly runs, these scripts run between 12:14 a.m. and 12:44 a.m.

Super Server SuSE uses inetd by default, although xinetd is also available.

Mail Server SuSE uses Postfix as the default mail server. Its configuration files reside in /etc/postfix.

Network Configuration SuSE uses the /etc/init.d/network SysV startup script to start basic networking features. This script relies on variables stored in files in the /etc/sysconfig/network directory tree. Therefore, permanently changing some networking details requires editing these files.

Local Startup Files If you want to change something about the system configuration that doesn't fit in well in the default script set, you can edit the /etc/init.d/boot.local script. SuSE executes this script after running the scripts in /etc/init.d/boot.d but before running the scripts for the startup runlevel.

As with other Linux distributions that use GUI configuration tools, you can modify configuration files to alter the system as you see fit; however, the automatic tools may choke or ignore your changes if those changes don't conform to the standards the tools expect.

Team LiB

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