E

e2label command

defined, 803

troubleshooting with, 753–754, 755

edquota command, 294–298, 803

egrep command, 23

electronic mail. See e-mail

elinks text browser, 51

emacs

defined, 803

errors starting in rescue mode, 8

e-mail, 586–611. See also e-mail clients; sendmail

activating Dovecot, 590–591

exam topics on, 586

finding mail server packages, 589

installing mail server packages, 588–589

lab questions and answers, 606–607, 609–611

mail server components, 587

mail utility, 49–50, 600–601

overview, 586

Postfix, 598–599

reading mail messages, 601

reception with Dovecot, 589–591

selecting e-mail system, 599–603

self test and answers, 605–606, 608–609

sendmail configuration, 592–597

summarized, 603

two-minute drill, 604

e-mail clients, 600–602

command-line mail utility, 49–50, 600–601

configuration process for, 49

mail group "alias" lists, 50, 602

reading mail messages, 50, 601

enabling

firewall access for kernels, 705

IP masquerading, 704–705

ports for DNS communications, 564, 565

Telnet with xinetd, 620

encrypted communications and SSH, 621–622

enforcing mode for SELinux, 707, 709

environment variables

setting defaults with env command, 27

setting shell, 29

environments

defined, 803

hidden files in home directory, 285–287

error messages

found in troubleshooting scenarios, 733

requiring links package, 448

running partprobe command, 195

errors

common configuration file, 730–731

DNS, 573–574

finding GRUB configuration, 152–155

module errors in boot loader, 750–751

pico errors starting in rescue mode, 8

running yum command from local system, 239

troubleshooting Apache, 472–473

using /etc/exports files, 497–498

/etc directories

init scripts hard linked to, 162

system-wide configuration files located in, 287

/etc/auto.master file, 204

/etc/auto.misc file, 204–205

/etc/auto.net file, 205–206

/etc/bashrc file, 287

/etc/dovecot.conf file, 590

/etc/exports file

commands in NFS Server Configuration tool and, 500

creating shared directory in, 508–509

errors using, 497–498

/etc/fstab

activating disk quotas in, 293–294

defined, 803

mounting filesystems with, 200–201

options for mounting directories, 201, 202

remote directory mounting with NFS client during booting, 511

/etc/groups, 301

/etc/hosts file, 42–43, 560

/etc/hosts.allow file, 694, 695

/etc/hosts.conf file, 43

/etc/hosts.deny file, 694–696

/etc/inittab

configuring virtual consoles from, 160

defined, 803

determining runlevels with, 159–160

troubleshooting scenarios for, 731, 732

understanding boot process in, 164

/etc/ldap.conf file, 315

/etc/mail/sendmail.mc file, 594, 595

/etc/mail/sendmail.cf file, 594, 595

/etc/mail/submit.cf file, 594

/etc/named.caching-nameserver.conf file, 563

/etc/nologin file, 309

/etc/nssswitch.conf file, 43

/etc/openldap/ldap.conf file, 315

/etc/pam.d/login, 308–310

/etc/pam.d/system-auth file, 309

/etc/passwd file, 31–32, 275

/etc/profile.d/, 289

/etc/profile file, 288–289

/etc/rc.d files, 164

/etc/rc.dirc.sysinit files, 164

/etc/rc.sysinit script, 293

/etc/resolv.conf file, 43, 560

/etc/samba/smb.conf file

editing, 523–524

misspelled variables in, 533

testing changes to, 542

variables for, 529

/etc/shadow file, 33–34, 283–284

/etc/skel directory, 35, 285–287

/etc/squid/squid.conf file, 478–480

/etc/sysconfig directory

configuring files in, 169

configuring name resolution with /etc/sysconfig/network file, 42

exam tips for understanding of, 331

non-network files in, 170

/etc/sysconfig/iptables file, 700

/etc/sysconfig/networking/devices directory, 332

/etc/sysconfig/networking/profiles/ default directory, 332

/etc/sysconfig/network-scripts directory, 331, 332–333

/etc/sysconfig/selinux file, 707

/etc/sysconfig/squid file, 478

/etc/X11 /prefdm file, 803

/etc/X11 /xorg.conf file, 660–662

/etc/xinetd.conf file, 616

Ethernet Device dialog box, 335

exam. See also lab questions and answers; self test and answers

administrator login for, 273–274

based on x86 architecture, 75

books helpful for, 2

boot process topics, 144, 164

configuring client connections in

NIS and LDAP, 313

creating partitions with care, 102

dealing with hardware problems, 158

desktop environment selection on, 112

device name associated with partitions, 98

DHCP knowledge required, 627

DNS topics on, 558, 567

e-mail topics on, 586, 600–602

filesystem administration on, 184

following instructions for IP

addresses, 108

given credit only if changes survive reboot, 415

GUI access during

Troubleshooting, 282

hardware issues in, 5

HTTP Web sites configured on, 458

importance of installation on, 70, 71, 88

index.html files to be created during, 469

installation and configuration requirements for, 272

installing GUI for, 120

kernel management, 376, 389, 393

kickstart preparation for, 222, 245

looking up Samba variables during, 529

LVM skills needed on, 376, 418

managing RPM packages, 222

mounting Zip drives, 203

network configuration tips for, 331, 337

network services on, 445, 495, 615

PAM configuration files on, 312

preparing for, 2–3

prerequisite skills for, 4

preventing unauthorized system access, 700

RAID on, 376, 412

Red Hat Network on, 234

reinstalls during, 126

RHCE troubleshooting skills, 748–759

RHCT troubleshooting skills, 742–748

runlevels of activated service for, 169

Samba configuration on, 524

Sample Exam 1, 768–781

Sample Exam 2, 784–782

SELinux topics on, 81, 184, 208, 708

setting up users, 125

source RPM familiarity for, 230

SSH, DHCP, and NTP network services on, 615

system administration tools used on, 330

system configuration during installation "dead time", 120

time server configuration on, 124

tips for users of other Unix-style systems, 255

troubleshooting skills, 728, 729, 742–759

upgrading kernels, 389

virtual hosts, 467, 470

when to install Virtualization package, 109

Xen, 377

X Window System on, 650, 651

executable virtual host files, 470

exim, 586

expanding logical volumes, 758

exportfs command, 804

exporting NFS directories

activating list of exports, 498–499

/etc/exports configuration file for, 497–498

overview, 496

Express Cards, 78, 79, 804

Extended Internet Services Daemon. See xinetd