Linux Server Security, Second Edition

This is the Title of the Book, eMatter Edition

Copyright © 2007 O’Reilly & Associates, Inc. All rights reserved.

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Chapter 3: Hardening Linux and Using iptables

To list all the startup services on my Red Hat system, I simply enter chkconfig --list.

For each script in /etc/rc.d, chkconfig lists that script’s startup status (on or off) at each

runlevel. The output of Example 3-3 has been truncated for readability.

To disable isdn in runlevel 2, I’d execute the commands shown in Example 3-4.

(The second command,

chkconfig --list isdn, is optional but useful in showing the

results of the first.) To remove isdn’s startup script from all runlevels, I’d use the

command:

chkconfig -–del isdn

Disabling services in SUSE

SUSE Linux introduced a syntax-compatible version of chkconfig in SUSE 8.1 (it’s

actually a frontend to its own insserv command) but still uses its own format for init

scripts (Example 3-5).

Example 3-2. chkconfig usage message

[mick@woofgang mick]# chkconfig --help

chkconfig version 1.2.16 - Copyright (C) 1997-2000 Red Hat, Inc.

This may be freely redistributed under the terms of the GNU Public License.

usage: chkconfig --list [name]

chkconfig --add <name>

chkconfig --del <name>

chkconfig [--level <levels>] <name> <on|off|reset>)

Example 3-3. Listing all startup scripts’ configuration

[root@woofgang root]# chkconfig --list

nfs 0:off 1:off 2:off 3:off 4:off 5:off 6:off

microcode_ctl 0:off 1:off ...