Linux Administration Handbook

by Nemeth, Evi; Snyder, Garth; Hein, Trent R.

• ISBN13: 9780130084668
• ISBN10: 0130084662
• Edition: 1st
• Format: Paperback
• Copyright: 2002-01-01
• Publisher: Prentice Hall PTR

Summary

This is the first Linux administration guide specifically focused on preparing students to administer large-scale enterprise systems. Written by the well-respected authors of Unix System Administration Handbook, Third Edition- the classic book that has taught Unix system administration to generations of students-Linux System Administration Handbook covers every key aspect of running systems utilizing today's leading Linux distributions for university and enterprise environments: RedHat, Debian, and SuSe.

Table of Contents

Foreword	xxvii
Preface	xxviii
Acknowledgments	xxxi
BASIC ADMINISTRATION
Where to Start	1	(17)
Suggested background	2	(1)
Linux's relationship to UNIX	2	(1)
Linux and UNIX history	3	(1)
Linux distributions	4	(2)
So what's the best distribution?	5	(1)
Distribution-specific administration tools	6	(1)
Notation and typographical conventions	6	(1)
System-specific information	7	(1)
Where to go for information	7	(4)
Organization of the man pages	9	(1)
man: read manual pages	10	(1)
Other sources of Linux information	10	(1)
How to find and install software	11	(2)
Essential tasks of the system administrator	13	(2)
Adding and removing users	13	(1)
Adding and removing hardware	13	(1)
Performing backups	13	(1)
Installing new software	13	(1)
Monitoring the system	14	(1)
Troubleshooting	14	(1)
Maintaining local documentation	14	(1)
Auditing security	14	(1)
Helping users	14	(1)
System administration under duress	15	(1)
System Administration Personality Syndrome	15	(1)
Recommended reading	16	(1)
Exercises	17	(1)
Booting and Shutting Down	18	(21)
Bootstrapping	18	(4)
Automatic and manual booting	19	(1)
Steps in the boot Process	19	(1)
Kernal initialization	20	(1)
Hardware configuration	20	(1)
System processes	20	(1)
Operator intervention (manual boot only)	21	(1)
Execution of startup scripts	21	(1)
Multiuser operation	21	(1)
Booting PCs	22	(1)
How a PC is different from proprietary hardware	22	(1)
The PC boot Process	22	(1)
Boot loaders: LILO and GRUB	23	(4)
LILO: the traditional Linux boot loader	23	(1)
GRUB: the GRand Unified Boot loader	24	(1)
Multibooting on PCs	25	(1)
Multibooting gotchas	26	(1)
LILO multiboot configuration	27	(1)
Booting single-user mode	27	(1)
Startup scripts	28	(7)
init and run levels	29	(2)
Red Hat startup scripts	31	(2)
SuSE startup scripts	33	(2)
Debian startup scripts	35	(1)
Rebooting and shutting down	35	(3)
Turning off the power	36	(1)
shutdown: the genteel way to halt the system	36	(1)
halt: a simpler way to shut down	37	(1)
reboot: quick and dirty restart	37	(1)
telinit: change init's run level	37	(1)
Poweroff: ask Linux to turn off the power	37	(1)
Exercises	38	(1)
Rootly Powers	39	(9)
Ownership of files and processes	39	(2)
The superuser	41	(1)
Choosing a root password	41	(1)
Becoming root	42	(4)
su: substitute user identity	43	(1)
sudo: a limited su	43	(3)
Other pseudo-users	46	(1)
bin: legacy owner of system commands	46	(1)
daemon: owner of unprivilaged system software	46	(1)
nobody: the generic NFS user	46	(1)
Exercises	47	(1)
Controlling Processes	48	(15)
Components of a process	48	(2)
PID: process ID number	49	(1)
PPID: parent PID	49	(1)
UID and EGID: real and effective user ID	49	(1)
GID and EGID: real and effective group ID	50	(1)
Niceness	50	(1)
Control terminal	50	(1)
The life cycle of a process	50	(1)
Signals	51	(3)
kill and killall: send signals	54	(1)
Process states	55	(1)
nice and renice: influence scheduling priority	55	(1)
ps: monitor processes	56	(2)
top: monitor processes even better	58	(1)
Runaway processes	59	(2)
Exercises	61	(2)
The Filesystem	63	(18)
Pathnames	64	(1)
Mounting and unmounting filesystems	65	(2)
The organization of the file tree	67	(2)
File types	69	(4)
Regular files	70	(1)
Directories	70	(1)
Character and block device files	71	(1)
Local domain sockets	72	(1)
Named pipes	72	(1)
Symbolic links	72	(1)
File attributes	73	(7)
The setuid and setgid bits	73	(1)
The sticky bit	73	(1)
The permission bits	73	(1)
Viewing file attributes	74	(2)
chmod: change permissions	76	(1)
chown: change ownership and group	77	(1)
umask: assign default permissions	78	(1)
Bonus flags	78	(2)
Exercises	80	(1)
Adding New Users	81	(17)
The /etc/passwd file	81	(6)
Login name	82	(1)
Encrypted password	83	(2)
UID number	85	(1)
Default GID number	85	(1)
GECOS field	86	(1)
Home directory	86	(1)
Login shell	86	(1)
The /etc/shadow file	87	(1)
The /etc/group file	88	(2)
Adding users	90	(4)
Editing the passwd and shadow files	90	(1)
Setting an initial password	91	(1)
Creating the user's home directory	91	(1)
Copying in the default startup files	91	(2)
Setting the user's mail home	93	(1)
Editing the /etc/group file	93	(1)
Setting disk quotas	93	(1)
Verifying the new login	93	(1)
Recording the user's status and contact information	94	(1)
Removing users	94	(1)
Disabling logins	95	(1)
Account management utilities	95	(2)
Exercises	97	(1)
Serial Devices	98	(26)
Serial standards	98	(4)
Alternative connectors	102	(5)
The mini DIN-8 variant	102	(1)
The DB-9 variant	103	(1)
The RJ-45 variant	104	(1)
The Yost standard for RJ-45 wiring	104	(3)
Hard and soft carrier	107	(1)
Hardware flow control	107	(1)
Cable length	108	(1)
Serial device files	108	(1)
setserial: tell the driver about serial port parameters	109	(1)
Software configuration for serial devices	110	(1)
Configuration of hardwired terminals	110	(4)
The login process	110	(1)
The /etc/inittab file	111	(2)
Terminal support: the termcap and terminfo databases	113	(1)
Special characters and the terminal driver	114	(1)
stty: set terminal options	115	(1)
tset: set options automatically	116	(1)
How to unwedge a terminal	117	(1)
Modems	117	(3)
Modulation, error correction, and data compression protocols	118	(1)
minicom: dial out	119	(1)
Bidirectional modems	119	(1)
Debugging a serial line	120	(1)
Other common I/O ports	120	(3)
Parallel ports	121	(1)
USB: the Universal Serial Bus	121	(2)
Exercises	123	(1)
Adding a Disk	124	(28)
Disk interfaces	124	(8)
The SCSI interface	125	(5)
The IDE interface	130	(1)
Which is better, SCSI or IDE?	131	(1)
Disk geometry	132	(2)
An Overview of the disk installation procedure	134	(5)
Connecting the disk	134	(1)
Formatting the disk	135	(1)
Labeling and partitioning the disk	135	(2)
Establishing logical volumes	137	(1)
Linux filesystems	138	(1)
The ext2 and ext3 filesystems	139	(4)
Setting up ext3fs extensions	140	(1)
Setting up automatic mounting	141	(2)
Enabling swapping	143	(1)
fsck: check and repair filesystems	143	(2)
Adding a disk to Linux: a step-by-step guide	145	(5)
Exercises	150	(2)
Periodic Processes	152	(7)
cron: schedule commands	152	(1)
The format of crontab files	153	(2)
Crontab management	155	(1)
Some common uses for cron	156	(2)
Cleaning the filesystem	156	(1)
Network distribution of configuration files	157	(1)
Rotating log files	157	(1)
Exercises	158	(1)
Backups	159	(40)
Motherhood and apple pie	160	(4)
Perform all dumps from one machine	160	(1)
Label your tapes	160	(1)
Pick a reasonable backup interval	160	(1)
Choose filesystems carefully	161	(1)
Make daily dumps fit on one tape	161	(1)
Make filesystems smaller than your dump device	161	(1)
Keep tapes off-site	162	(1)
Protect your backups	162	(1)
Limit activity during dumps	162	(1)
Check your tapes	162	(1)
Develop a tape life cycle	163	(1)
Design your data for backups	164	(1)
Prepare for the worst	164	(1)
Backup devices and media	164	(6)
Floppy disks	165	(1)
Super floppies	165	(1)
CD-R and CD-RW	166	(1)
Removable hard disks	166	(1)
8mm cartridge tapes	166	(1)
DAT (4mm) cartridge tapes	167	(1)
Travan tapes	167	(1)
DLT	167	(1)
AIT	167	(1)
Mammoth	168	(1)
Jukeboxes, stackers, and tape libraries	168	(1)
Hard disks	169	(1)
Summary of media types	169	(1)
What to buy	170	(1)
Setting up an incremental backup regime with dump	170	(4)
Dumping filesystems	170	(3)
Dump sequences	173	(1)
Restoring from dumps with restore	174	(4)
Restoring individual files	174	(2)
Restoring entire filesystems	176	(2)
Dumping and restoring for upgrades	178	(1)
Using other archiving programs	178	(2)
tar: package files	178	(1)
cpio: archiving utility from ancient times	179	(1)
dd: twiddle bits	179	(1)
volcopy: duplicate filesystems	180	(1)
Using multiple files on a single tape	180	(1)
Robot at your service?	181	(1)
Amanda	181	(14)
The architecture of Amanda	181	(1)
Amanda setup	182	(1)
The amanda.conf file	183	(5)
The disklist file	188	(2)
Amanda log files	190	(1)
Amanda debugging	190	(3)
File restoration from an Amanda backup	193	(2)
Alternatives to Amanda: other open source backup packages	195	(1)
Commercial backup products	195	(2)
ADSM/TSM	196	(1)
Veritas	196	(1)
Legato	196	(1)
Other alternatives	197	(1)
Recommended reading	197	(1)
Exercises	197	(2)
Syslog And Log Files	199	(20)
Logging policies	199	(3)
Throwing away log files	199	(1)
Rotating log files	200	(1)
Archiving log files	201	(1)
Linux log files	202	(3)
Special log files	203	(1)
Kernel and boot-time logging	204	(1)
logrotate: manage log files	205	(1)
Syslog: the system event logger	206	(10)
Configuring syslogd	207	(3)
Config file examples	210	(2)
Sample syslog output	212	(1)
Designing a logging scheme for your site	213	(1)
Software that uses syslog	214	(1)
Debugging syslog	214	(1)
Using syslog from programs	215	(1)
Condensing log files to useful information	216	(2)
Exercises	218	(1)
Drivers And The Kernel	219	(18)
Kernel adaptation	220	(1)
Why configure the kernel?	220	(1)
Configuration methods	221	(1)
Tuning a Linux Kernel	221	(1)
Adding device drivers	222	(2)
Device numbers	223	(1)
Adding a Linux device driver	224	(2)
Device files	226	(1)
Naming convention for devices	227	(1)
Loadable Kernel modules	227	(2)
Building a Linux Kernel	229	(3)
Building the Linux Kernel binary	231	(1)
Don't fix it if it ain't broken	232	(1)
Recommended reading	232	(1)
Exercises	233	(4)
NETWORKING
TCP/IP Networking	237	(68)
TCP/IP and the Internet	238	(3)
A brief history lesson	238	(1)
How the Internet is managed today	239	(1)
Network standards and documentation	240	(1)
Networking road map	241	(1)
Packets and encapsulation	242	(5)
The link layer	243	(2)
Packet addressing	245	(2)
Ports	247	(1)
Address types	247	(1)
IP addresses: the gory details	247	(13)
IP address classes	248	(1)
Subnetting and netmasks	248	(3)
The IP address crisis	251	(1)
CIDR: Classless Inter-Domain Routing	252	(2)
Address allocation	254	(1)
Private addresses and NAT	255	(2)
IPv6 addressing	257	(3)
Routing	260	(2)
Routing tables	260	(1)
ICMP redirects	261	(1)
ARP: The address resolution protocol	262	(2)
Adding a machine to a network	264	(10)
Assigning hostnames and IP addresses	265	(1)
ifconfig: configure network interfaces	266	(3)
mii-tool: configure autonegotiation and other media-specific options	269	(1)
route: configure static routes	270	(2)
Default routes	272	(1)
Configuring DNS	272	(1)
The Linux networking stack	273	(1)
Distribution-specific network configuration	274	(4)
Network configuration for Red Hat	274	(2)
Network configuration for SuSE	276	(1)
Network configuration for Debian	277	(1)
Network configuration with a GUI	278	(1)
DHCP: the Dynamic Host Configuration Protocol	278	(6)
DHCP software	279	(1)
How DHCP works	280	(1)
ISC's DHCP server	280	(2)
DHCP configuration for Red Hat	282	(1)
DHCP configuration for SuSE	283	(1)
DHCP configuration for Debian	283	(1)
Linux dynamic reconfiguration and tuning	284	(2)
Security issues	286	(3)
IP forwarding	286	(1)
ICMP redirects	286	(1)
Source routing	286	(1)
Broadcast pings and other forms of directed broadcast	286	(1)
IP spoofing	287	(1)
Host-based firewalls	288	(1)
Virtual private networks	288	(1)
Security-related kernel variables	288	(1)
Linux NAT (IP masquerading)	289	(1)
PPP: the Point-to-Point Protocol	290	(11)
Addressing PPP Performance issues	291	(1)
Connecting to a network with PPP	291	(1)
Making your host speak PPP	292	(1)
Controlling PPP links	292	(1)
Finding a host to talk to	292	(1)
Assigning an address	292	(1)
Routing	293	(1)
Ensuring security	293	(1)
Using terminal servers	293	(1)
Using chat scripts	293	(1)
Linux PPP configuration	294	(7)
Linux networking quirks	301	(1)
Recommended reading	302	(2)
Exercises	304	(1)
Routing	305	(30)
Packet forwarding: a closer look	306	(2)
Routing daemons and routing protocols	308	(3)
Distance-vector protocols	309	(1)
Link-state protocols	309	(1)
Cost metrics	310	(1)
Interior and exterior protocols	311	(1)
Protocols on parade	311	(3)
RIP: Routing Information Protocol	312	(1)
RIP-2: Routing Information Protocol, version 2	312	(1)
OSPF: Open Shortest Path First	313	(1)
IGRP and EIGRP: Interior Gateway Routing Protocol	313	(1)
IS-IS: the ISO ``standard''	313	(1)
MOSPF, DVMRP, and PIM: multicast routing protocols	314	(1)
Router Discovery Protocol	314	(1)
routed: RIP yourself a new hole	314	(1)
gated: a better routing daemon	315	(14)
gated startup and control	315	(1)
Tracing	316	(1)
The gated configuration file	316	(1)
Option configuration statements	317	(1)
Network interface definitions	318	(2)
Other miscellaneous definitions	320	(1)
Protocol configuration for RIP	321	(1)
Some preliminary background on OSPF	322	(2)
Protocol configuration for OSPF	324	(1)
Protocol configuration for ICMP redirects	325	(1)
Static routes	325	(1)
Exported routes	326	(1)
A complete gated configuration example	327	(2)
Routing strategy selection criteria	329	(1)
Cisco routers	330	(2)
Recommended reading	332	(2)
Exercises	334	(1)
Network Hardware	335	(22)
LAN, WAN, or MAN?	335	(1)
Ethernet: the common LAN	336	(8)
How Ethernet works	336	(1)
Ethernet topology	337	(1)
Unshielded twisted pair	338	(2)
Connecting and expanding Ethernets	340	(4)
Wireless: the nomad's LAN	344	(1)
FDDI: the disappointing and expensive LAN	345	(1)
ATM: the promised (but sorely defeated) LAN	346	(1)
Frame relay: the sacrificial WAN	347	(1)
ISDN: the indigenous WAN	347	(1)
DSL and cable modems: the people's WAN	348	(1)
Where is the network going?	349	(1)
Network testing and debugging	349	(1)
Building wiring	350	(1)
UTP cabling options	350	(1)
Connections to offices	351	(1)
Wiring standards	351	(1)
Network design issues	351	(3)
Network architecture vs. building architecture	352	(1)
Existing networks	353	(1)
Expansion	353	(1)
Congestion	353	(1)
Maintenance and documentation	353	(1)
Management issues	354	(1)
Recommended vendors	355	(1)
Cables and connectors	355	(1)
Test equipment	355	(1)
Routers/switches	356	(1)
Recommended reading	356	(1)
Exercises	356	(1)
The Domain Name System	357	(111)
DNS for the impatient: adding a new machine	357	(2)
The history of DNS	359	(1)
Who needs DNS?	360	(1)
What's new in DNS	361	(1)
The DNS namespace	362	(6)
Masters of their domains	365	(1)
Selecting a domain name	366	(1)
Domain bloat	367	(1)
Registering a second-level domain name	367	(1)
Creating your own subdomains	367	(1)
The BIND software	368	(5)
Versions of BIND	368	(1)
Finding out what version you have	369	(1)
Components of BIND	370	(1)
named: the BIND name server	370	(1)
Authoritative and caching-only servers	371	(1)
Recursive and nonrecursive servers	372	(1)
The resolver library	373	(1)
Shell interfaces to DNS	373	(1)
How DNS works	373	(3)
Delegation	373	(2)
Caching and efficiency	375	(1)
The extended DNS protocol	376	(1)
BIND client issues	376	(4)
Resolver configuration	377	(2)
Resolver testing	379	(1)
Impact on the rest of the system	380	(1)
BIND server configuration	380	(18)
Hardware requirements	380	(1)
named startup	381	(1)
Configuration files	381	(2)
The include statement	383	(1)
The options statement	383	(6)
The acl statement	389	(1)
The server statement	389	(1)
The logging statement	390	(1)
The zone statement	391	(3)
The key statement	394	(1)
The trusted-keys statement	394	(1)
The controls statement	395	(2)
Split DNS and the BIND 9 view statement	397	(1)
BIND configuration examples	398	(10)
A home Linux box	398	(2)
A small security company	400	(3)
A university department	403	(5)
The DNS database	408	(23)
Resource records	408	(3)
The SOA record	411	(2)
NS records	413	(1)
A records	414	(1)
PTR records	414	(1)
MX records	415	(2)
CNAME records	417	(1)
The CNAME hack	418	(2)
LOC records	420	(1)
SRV records	421	(1)
TXT records	422	(1)
IPv6 resource records	422	(1)
IPv6 address records	423	(1)
IPv6 reverse records	424	(3)
Commands in zone files	427	(2)
The localhost zone	429	(1)
Glue records: links between zones	429	(2)
Updating zone files	431	(4)
Zone transfers	432	(1)
Dynamic updates	433	(2)
Security issues	435	(12)
Access control lists revisited	436	(1)
Confining named	437	(1)
Secure server-to-server communication with TSIG and TKEY	438	(2)
DNSSEC	440	(6)
Microsoft bad, Linux good	446	(1)
Testing and debugging	447	(13)
Logging	448	(4)
Debug levels	452	(1)
Debugging with ndc	453	(1)
Statistics for BIND 8	454	(1)
Statistics for BIND 9	455	(1)
Debugging with nslookup, dig, and host	456	(2)
Lame delegations	458	(2)
Loose ends	460	(2)
The hints file	460	(1)
Localhost configuration	461	(1)
Host management tools	461	(1)
DNS for systems not on the Internet	462	(1)
Distribution specifics	462	(2)
Versions	462	(1)
BIND files	462	(1)
The name server switch file	463	(1)
Configuration files	463	(1)
Recommended reading	464	(2)
Mailing lists and newsgroups	464	(1)
Books and other documentation	464	(1)
On-line resources	464	(1)
The RFCs	465	(1)
Exercises	466	(2)
The Network File System	468	(19)
General information about NFS	468	(4)
NFS protocol versions	468	(1)
Choice of transport	469	(1)
File locking	469	(1)
Disk quotas	470	(1)
Cookies and stateless mounting	470	(1)
Naming conventions for shared filesystems	470	(1)
Security and NFS	471	(1)
Root access and the nobody account	471	(1)
Server-side NFS	472	(3)
The exports file	473	(1)
nfsd: serve files	474	(1)
Client-side NFS	475	(3)
Mounting remote filesystems at boot time	477	(1)
Secure port restrictions	478	(1)
nfsstat: dump NFS statistics	478	(1)
Dedicated NFS file servers	479	(1)
Automatic mounting	479	(1)
automount	480	(3)
The master file	481	(1)
Map files	482	(1)
Executable maps	482	(1)
amd: a more sophisticated automounter	483	(2)
amd maps	483	(2)
Starting amd	485	(1)
Stopping amd	485	(1)
Recommended reading	485	(1)
Exercises	486	(1)
Sharing System Files	487	(24)
What to share	488	(1)
nscd: cache the results of lookups	489	(1)
Copying files around	489	(7)
rdist: push files	490	(3)
rsync: transfer files more securely	493	(2)
Pulling files	495	(1)
NIS: the Network Information Service	496	(8)
Netgroups	497	(1)
Prioritizing sources of administrative information	498	(1)
Advantages and disadvantages of NIS	499	(1)
How NIS works	500	(2)
Setting up an NIS domain	502	(2)
NIS+: son of NIS	504	(1)
LDAP: the Lightweight Directory Access Protocol	505	(5)
LDAP documentation and specifications	506	(1)
Hands-on LDAP	507	(1)
Configuring an OpenLDAP server	507	(1)
Populating your server	508	(1)
Setting up an LDAP client	509	(1)
LDAP and security	509	(1)
Exercises	510	(1)
Electronic Mail	511	(116)
Mail systems	513	(4)
User agents	513	(2)
Transport agents	515	(1)
Delivery agents	516	(1)
Message stores	516	(1)
Access agents	516	(1)
Mail submission agents	517	(1)
The anatomy of a mail message	517	(6)
Mail addressing	518	(1)
Reading mail headers	519	(4)
Mail philosophy	523	(4)
Using mail servers	523	(2)
Using mail homes	525	(1)
Using IMAP or POP	526	(1)
Mail aliases	527	(14)
Getting mailing lists from files	529	(1)
Mailing to files	530	(1)
Mailing to programs	531	(1)
Examples of aliases	531	(1)
Mail forwarding	532	(2)
The hashed alias database	534	(1)
Mailing lists and list wrangling software	535	(3)
LDAP: the Lightweight Directory Access Protocol	538	(3)
sendmail: ringmaster of the electronic mail circus	541	(9)
The history of sendmail	541	(1)
Vendor-supplied versions of sendmail	542	(1)
Sendmail installation from sendmail.org	543	(3)
Installing sendmail on Debian systems	546	(1)
The switch file	546	(1)
Modes of operation	546	(2)
The mail queue	548	(2)
sendmail configuration	550	(4)
Using the m4 preprocessor	551	(1)
The sendmail configuration pieces	552	(1)
Building a configuration file from a sample .mc file	553	(1)
Changing the sendmail configuration	554	(1)
Basic sendmail configuration primitives	554	(4)
The VERSIONID macro	554	(1)
The OSTYPE macro	555	(2)
The DOMAIN macro	557	(1)
The MAILER macro	557	(1)
Fancier sendmail configuration primitives	558	(15)
The Feature macro	559	(1)
The use_cw_file feature	559	(1)
The redirect feature	560	(1)
The always_add_domain feature	560	(1)
The nocanonify feature	560	(1)
Tables and databases	561	(2)
The mailertable feature	563	(1)
The genericstable feature	563	(1)
The virtusertable feature	564	(1)
The Idap_routing feature	565	(1)
Masquerading and the MASQUERADE_AS macro	566	(1)
The MAIL_HUB and SMART_HOST macros	567	(1)
Masquerading and routing	568	(1)
The nullclient feature	568	(2)
The local_Imtp and smrsh features	570	(1)
The local_procmail feature	570	(1)
The LOCAL_* macros	571	(1)
Configuration options	571	(2)
Configuration file examples	573	(15)
A Computer science student's home machine	573	(2)
A small but sendmail-clueful company	575	(3)
Another master/client example	578	(3)
Red Hat sendmail configuration	581	(2)
SuSe sendmail configuration	583	(3)
Debian sendmail configuration	586	(2)
Spam-related features in sendmail	588	(15)
Relaying	590	(2)
The access database	592	(3)
Blacklisting users or sites	595	(1)
Header checking	596	(1)
Miltering: mail filtering	597	(1)
Handling spam	598	(1)
Spam examples	599	(3)
Spam Assassin	602	(1)
Security and sendmail	603	(8)
Ownerships	603	(1)
Permissions	604	(1)
Safer mail to files and programs	605	(1)
Privacy options	606	(1)
Running a chrooted sendmail (for the truly paranoid)	607	(1)
Denial of service attacks	607	(1)
Forgeries	608	(1)
Message privacy	609	(1)
SASL: the Simple Authentication and Security Layer	610	(1)
sendmail performance	611	(4)
Delivery modes	611	(1)
Queue groups and envelope splitting	611	(2)
Queue runners	613	(1)
Load average controls	613	(1)
Undeliverable messages in the queue	613	(2)
Kernel tuning	615	(1)
sendmail statistics, testing, and debugging	615	(5)
Testing and debugging	616	(1)
Verbose delivery	617	(1)
Talking in SMTP	618	(1)
Logging	619	(1)
The Exim Mail System	620	(3)
History	621	(1)
Exim on Debian	621	(1)
Exim configuration	621	(1)
Exim/sendmail similarities	622	(1)
Recommended reading	623	(2)
Exercises	625	(2)
Network Management and Debugging	627	(23)
Troubleshooting a network	628	(1)
ping: check to see if a host is alive	629	(2)
traceroute: trace IP packets	631	(2)
netstat: get tons o' network statistics	633	(4)
Monitoring the status of network connections	633	(2)
Inspecting interface configuration information	635	(1)
Examining the routing table	636	(1)
Viewing operational statistics for various network protocols	636	(1)
Packet sniffers	637	(2)
tcpdump: king of sniffers	638	(1)
Ethereal: visual sniffer	639	(1)
Network management protocols	639	(2)
SNMP: the Simple Network Management Protocol	641	(2)
SNMP organization	641	(1)
SNMP protocol operations	642	(1)
RMON: remote monitoring MIB	643	(1)
The NET-SMNP agent	643	(1)
Network management applications	644	(4)
The NET-SNMP tools	645	(1)
MRTG: the Multi-Router Traffic Grapher	646	(1)
NOCOL: Network Operation Center On-Line	646	(1)
Commercial management platforms	647	(1)
Recommended reading	648	(1)
Exercises	649	(1)
Security	650	(43)
Is Linux secure?	651	(1)
Linux security, the CliffsNotes version	652	(2)
Packet filtering	652	(1)
Unnecessary services	652	(1)
Software patches	652	(1)
Backups	652	(1)
Passwords	653	(1)
Vigilance	653	(1)
General philosophy	653	(1)
How security is compromised	654	(1)
Security problems in the /etc/passwd and /etc/shadow files	655	(4)
Password checking and selection	655	(1)
PAM: cooking spray or authentication wonder?	656	(1)
Shadow passwords	657	(1)
Group logins and shared logins	658	(1)
Password aging	658	(1)
User shells	658	(1)
Rootly entries	658	(1)
Setuid programs	659	(1)
Important file permissions	660	(1)
Miscellaneous security issues	661	(3)
Remote event logging	661	(1)
Secure terminals	661	(1)
/etc/hosts.equiv and ~/.rhosts	661	(1)
rexecd and tftpd	662	(1)
fingerd	662	(1)
Security and NIS	662	(1)
Security and NFS	663	(1)
Security and sendmail	663	(1)
Security and backups	663	(1)
Trojan horses	663	(1)
Security power tools	664	(6)
nmap: scan network ports	664	(2)
ndiff: create nmap baselines and look for suspicious changes	666	(1)
SAINT: check networked systems for vulnerabilities	666	(1)
Nessus: next generation network scanner	667	(1)
crack: find insecure passwords	667	(1)
tcpd: protect Internet services	668	(1)
COPS: audit system security	668	(1)
tripwire: monitor changes to system files	669	(1)
Forensic tools	670	(1)
Cryptographic security tools	670	(6)
Kerberos: a unified approach to network security	671	(1)
PGP: Pretty Good Privacy	672	(1)
SSH: the secure shell	673	(2)
OPIE: One-time Passwords in Everything	675	(1)
Hardware tokens	675	(1)
Firewalls	676	(3)
Packet-filtering firewalls	676	(1)
How services are filtered	676	(1)
Service proxy firewalls	677	(1)
Stateful inspection firewalls	678	(1)
Firewalls: how safe are they?	678	(1)
Linux firewall features: IP tables	679	(4)
Virtual private networks (VPNs)	683	(1)
IPSEC tunnels	683	(1)
All I need is a VPN, right?	684	(1)
Sources of security information	684	(3)
CERT: a registered service mark of Carnegie Mellon University	685	(1)
SecurityFocus.com and the BugTraq mailing list	685	(1)
Crypto-Gram newsletter	685	(1)
SANS: the System Administration, Networking, and Security Institute	685	(1)
Distribution-specific security resources	686	(1)
Other mailing lists and web sites	686	(1)
Hardened Linux distributions	687	(1)
What to do when your site has been attacked	687	(2)
Recommended reading	689	(2)
Exercises	691	(2)
Web Hosting and Internet Servers	693	(18)
Web hosting	693	(1)
Web hosting basics	694	(3)
Uniform resource locators	695	(1)
How HTTP works	696	(1)
CGI scripting: generating content on the fly	696	(1)
Load balancing	697	(1)
HTTP server installation	697	(3)
Choosing a server	697	(1)
Installing Apache	698	(1)
Configuring Apache	699	(1)
Running Apache	700	(1)
High-performance hosting	700	(1)
Virtual interfaces	700	(3)
Configuring virtual interfaces	701	(1)
Telling Apache about a virtual interface	702	(1)
Caching and proxy servers	703	(1)
Setting up Squid	704	(1)
Anonymous FTP server setup	704	(3)
Exercises	707	(4)
BUNCH O' STUFF
Software Installation and Localization	711	(33)
Basic Linux installation	711	(1)
Automating installation	712	(10)
Netbooting PCs	712	(1)
PXE: the PC netbooting standard	713	(1)
Setting up PXE for Linux	713	(1)
Netbooting non-PCs	714	(1)
Kickstart: Red Hat's automated installer	714	(3)
YaST: SuSE's installation tool	717	(2)
SystemImager	719	(3)
Localization	722	(9)
Automation	723	(1)
Versioning your build	723	(1)
Rogue users and departments	724	(1)
Testing	725	(1)
Making changes undoable	726	(1)
Revision control	726	(1)
RCS: the Revision Control System	727	(2)
Documentation	729	(1)
Where to put local software	730	(1)
How much to install on client machines	731	(1)
Keeping your systems up to date with rsync or rdist	731	(2)
Package management	733	(4)
RPM packages	734	(1)
Debian packages	735	(1)
Automating package installation	736	(1)
The Red Hat Network	737	(1)
apt-get: automate downloading and installation	737	(5)
Configuring apt-get	739	(1)
An example /etc/apt/sources.list file	740	(1)
Using proxies to make apt-get scale	740	(1)
Setting up an internal APT server	740	(1)
Automating apt-get	741	(1)
Recommended reading	742	(1)
Exercises	743	(1)
Printing	744	(27)
Mini-glossary of printing terms	745	(1)
Linux printing systems	746	(1)
Types of printers	747	(1)
Serial and parallel printers	747	(1)
Network printers	747	(1)
Life without PostScript	748	(1)
LPD: the good ol' printing system	748	(12)
An overview of the printing process	748	(2)
Controlling the printing environment	750	(1)
lpd: the print spooler	750	(1)
lpr: submit print jobs	751	(1)
lpq: view the printing queue	751	(1)
lprm: remove print jobs	751	(1)
1pc: make administrative changes	752	(2)
The/etc/printcap file	754	(1)
printcap variables	755	(4)
printcap variables for serial devices	759	(1)
printcap extensions	760	(1)
Printing to something besides a printer	760	(1)
LPRng	760	(4)
The LPRng commands	761	(1)
/etc/Ipd.conf:configure Ipd	762	(1)
/etc/Ipd.perms: configure access control	762	(1)
Setting up the printcap file	763	(1)
Filters	763	(1)
Accounting	764	(1)
Adding a printer	764	(2)
Distribution-specific details	766	(1)
Debugging printing problems	766	(1)
Common printing software	767	(1)
ghostscript	767	(1)
mpage	767	(1)
enscript	768	(1)
Printer philosophy	768	(2)
Use printer accounting	768	(1)
Use banner pages only when necessary	768	(1)
Provide recycling bins	768	(1)
Provide previewers	769	(1)
Buy cheap printers	769	(1)
Secure your printer	769	(1)
Exercises	770	(1)
Maintenance And Environment	771	(11)
Maintenance basics	771	(1)
Maintenance contracts	772	(1)
On-site maintenance	772	(1)
Board swap maintenance	772	(1)
Warranties	773	(1)
Board-handling lore	773	(1)
Static electricity	773	(1)
Reseating boards	774	(1)
Monitors	774	(1)
Memory modules	774	(1)
Preventive maintenance	775	(1)
Environment	776	(2)
Temperature	776	(1)
Humidity	776	(1)
Office cooling	776	(1)
Machine room cooling	776	(2)
Temperature monitoring	778	(1)
Power	778	(1)
Remote power control	779	(1)
Racks	779	(1)
Tools	780	(1)
Exercises	781	(1)
Performance Analysis	782	(15)
What you can do to improve performance	783	(1)
Factors that affect performance	784	(1)
System performance checkup	785	(9)
Analyzing CPU usage	786	(2)
How Linux manages memory	788	(2)
Analyzing memory usage	790	(2)
Analyzing disk I/O	792	(2)
Help! My system just got really slow!	794	(2)
Recommended reading	796	(1)
Exercises	796	(1)
Cooperating with Windows	797	(13)
File and print sharing	797	(6)
NFS: the Network File System	798	(1)
CIFS: the Common Internet File System	798	(1)
SMBFS: mount remote CIFS shares	798	(1)
Samba: CIFS server for Linux	798	(2)
Installing and configuring Samba	800	(1)
Debugging Samba	801	(1)
Unified Windows and Linux login authentication	802	(1)
Secure terminal emulation with SSH	803	(1)
X Windows emulators	803	(1)
PC mail clients	804	(1)
PC backups	805	(1)
Dual booting	805	(1)
Mounting foreign filesystems with Linux	805	(1)
Running Windows applications under Linux	806	(1)
Linux (and UNIX) on Windows	807	(1)
PC hardware tips	807	(1)
Recommended reading	808	(1)
Exercises	809	(1)
Daemons	810	(17)
init: the primordial process	811	(1)
cron and atd: schedule commands	812	(1)
inetd and xinetd: manage daemons	812	(6)
Configuring inetd	813	(2)
Configuring xinetd	815	(2)
The services file	817	(1)
portmap/rpcbind: map RPC services to TCP and UDP ports	818	(1)
Kernel daemons	818	(1)
klogd: read kernel messages	818	(1)
File service daemons	818	(2)
rpc.nfsd: serve files	818	(1)
rpc.mountd: respond to mount requests	819	(1)
amd and automount: mount filesystems on demand	819	(1)
rpc.lockd and rpc.statd: manage NFS locks	819	(1)
rpciod: cache NFS blocks	819	(1)
rpc.rquotad: serve remote quotas	819	(1)
smbd: provide file and printing service to Windows clients	819	(1)
nmbd: NetBIOS name server	819	(1)
Administrative database daemons	820	(1)
ypbind: locate NIS servers	820	(1)
ypserv: NIS server	820	(1)
rpc.ypxfrd: transfer NIS databases	820	(1)
nscd: name service cache daemon	820	(1)
Internet daemons	820	(4)
talkd: connect to network chat service	820	(1)
sendmail: transport electronic mail	821	(1)
snmpd: provide remote network management service	821	(1)
rwhod: maintain remote user list	821	(1)
ftpd: file transfer server	821	(1)
popper: basic mailbox server	821	(1)
imapd: deluxe mailbox server	821	(1)
in.rlogind: remote login server	822	(1)
in.telnetd: yet another remote login server	822	(1)
sshd: secure remote login server	822	(1)
in.rshd: remote command execution server	822	(1)
in.rexecd: yet another command execution server	822	(1)
rsyncd: synchronize files among multiple hosts	822	(1)
routed: maintain routing tables	823	(1)
gated: maintain complicated routing tables	823	(1)
named: DNS server	823	(1)
syslogd: process log messages	823	(1)
in.fingerd: look up users	823	(1)
httpd: World Wide Web server	824	(1)
1pd: manage printing	824	(1)
Time synchronization daemons	824	(1)
timed: synchronize clocks	824	(1)
ntpd and xntpd: synchronize clocks even better	825	(1)
Booting and configuration daemons	825	(1)
dhcpd: dynamic address assignment	825	(1)
in.tftpd: trivial file transfer server	825	(1)
rpc.bootparamd: advanced diskless life support	825	(1)
Exercises	826	(1)
Policy And Politics	827	(42)
Linux culture	828	(2)
Mainstream Linux	829	(1)
Linux projects	830	(1)
Policy and procedure	830	(9)
Security policies	833	(1)
User policy agreements	834	(1)
Sysadmin policy agreements	835	(1)
Policy and procedures for emergency situations	836	(1)
Disaster planning	837	(1)
Miscellaneous tidbits	838	(1)
Legal issues	839	(9)
Liability	839	(1)
Encryption	840	(1)
Copyright	840	(2)
Privacy	842	(1)
Policy enforcement	843	(1)
Software licenses	844	(1)
Spam: unsolicited commercial email	845	(1)
Sysadmin surveys	846	(1)
SAGE salary survey	846	(1)
SANS salary survey	847	(1)
Scope of service	848	(1)
Trouble-reporting systems	849	(1)
Managing management	850	(1)
Hiring, firing, and training	851	(2)
Attitude adjustment	852	(1)
Operator wars	852	(1)
Iterative refinement	853	(1)
War stories and ethics	853	(6)
Boss's mistake #1	854	(1)
Boss's mistake #2	854	(1)
Which ones to fire	854	(1)
Engineers vs. IT department	855	(1)
Horndog Joe	855	(1)
Wedding invitations	856	(1)
Pornographic GIF images	856	(1)
Migrating data	857	(1)
Bill must die!	858	(1)
Second-hand stories from the World Trade Center	858	(1)
Local documentation	859	(1)
Procurement	860	(1)
Decommissioning hardware	861	(1)
Organizations, conferences, and other resources	862	(4)
LPI: the Linux Professional Institute	863	(1)
SAGE: the System Administrators Guild	864	(1)
SANS: the System Administration, Networking, and Security Institute	865	(1)
Mailing lists and web resources	865	(1)
Printed resources	865	(1)
Standards	866	(1)
LSB: the Linux Standard Base	866	(1)
POSIX	867	(1)
Sample documents	867	(1)
Recommended reading	867	(1)
Exercises	868	(1)
Colophon	869	(1)
Index	870

Excerpts

Preface Linux is a relatively new operating system in the world of computing. Born in the early 1990s, it has enjoyed tremendous publicity and support from the open source community. In many ways, Linux has come to represent the antimatter of an otherwise Microsoft-centric universe. Despite Linux's many achievements, it has yet to gain full acceptance in the world of "production computing." Once synonymous with big-iron mainframes, this environment is a world in which a few minutes of downtime can cost millions of dollars, dozens of jobs, or in extreme cases, lives. We think it's about time that Linux was accepted as a fully ordained member of this community. However, such acceptance can only develop with the help of a cavalry ofprofessionalLinux system administrators. We set out to write a book that would be the professional Linux system administrator's best friend. Where appropriate, we've adapted the proven concepts and materials from our popular book,UNIX System Administration Handbook. We've added a truckload of Linux-specific material and updated the rest, but much of the coverage remains similar. We hope you agree that the result is a high-quality guide to Linux administration that benefits from its experience in a past life. There are other books on Linux system administration, but none that provide the breadth and depth of material necessary to effectively use Linux in real-world business environments. Here are the features that distinguish our book: We take a practical approach. Our purpose is not to restate the contents of your manuals but rather to summarize our collective experience in system administration. This book contains numerous war stories and a wealth of pragmatic advice. This is not a book about how to run Linux at home, in your garage, or on your PDA. We describe the use of Linux in production environments such as businesses, government offices, and universities. We cover Linux networking in detail. It is the most difficult aspect of system administration and the area in which we think we can be of most help. We do not oversimplify the material. Our examples reflect true-life situations with all their warts and unsightly complications. In most cases, the examples have been taken directly from production systems. We cover three major Linux distributions. Our example distributions Like so many operating systems, Linux has grown and branched in several different directions. Although development of the kernel has remained surprisingly centralized, packaging and distribution of complete Linux operating systems is overseen by a variety of groups, each with its own agenda. We cover three Linux distributions in detail: Red Hat 7.2 SuSE 7.3 Debian 3.0 We chose these distributions because they are among the most popular and because they are representative of the Linux community as a whole. However, much of the material in this book applies to other mainstream distributions as well. We provide detailed information about each of these example distributions for every topic that we discuss. Comments specific to a particular operating system are marked with the distribution's logo. The organization of this book This book is divided into three large chunks: Basic Administration, Networking, and Bunch o' Stuff. Basic Administration provides a broad overview of Linux from a system administrator's perspective. The chapters in this section cover most of the facts and techniques needed to run a stand-alone Linux system. The Networking section describes the protocols used on Linux systems and the techniques used to set up, extend, and maintain networks. High-level network software is also covered here. Among the featured topics are the Domain Name System, the Network File System, routing,sendmail, and network management.

Rewards Program

Currently unavailable