Red Hat ENTERPRISE LINUX 4.5.0 - User manual

Red Hat Enterprise Linux 4.5.0
4.5.0
Reference Guide
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Red Hat Enterprise Linux 4.5.0

Red Hat Enterprise Linux 4.5.0: Reference Guide
Copyright ©2007 Red Hat, Inc.
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Red Hat Enterprise Linux 4.5.0

Introduction ............................................................................................................ xvii
1. Changes To This Manual ............................................................................. xvii
2. Finding Appropriate Documentation .............................................................xviii
2.1. Documentation For First-Time Linux Users ........................................xviii
2.2. For the More Experienced ...................................................................xx
2.3. Documentation for Linux Gurus ...........................................................xx
3. Document Conventions ................................................................................ xxi
4. More to Come ............................................................................................. xxii
4.1. We Need Feedback! .........................................................................xxiii
I. System Reference .................................................................................................. 1
1. Boot Process, Init, and Shutdown .................................................................... 3
1. The Boot Process .................................................................................. 3
2. A Detailed Look at the Boot Process ....................................................... 3
2.1. The BIOS ................................................................................... 3
2.2. The Boot Loader ......................................................................... 4
2.3. The Kernel .................................................................................. 5
2.4. The /sbin/init Program ............................................................ 6
3. Running Additional Programs at Boot Time .............................................. 8
4. SysV Init Runlevels ................................................................................ 9
4.1. Runlevels ................................................................................... 9
4.2. Runlevel Utilities ........................................................................10
5. Shutting Down ......................................................................................11
2. The GRUB Boot Loader ................................................................................13
1. Boot Loaders and System Architecture ...................................................13
2. GRUB ..................................................................................................13
2.1. GRUB and the x86 Boot Process ................................................13
2.2. Features of GRUB ......................................................................14
3. Installing GRUB ....................................................................................15
4. GRUB Terminology ...............................................................................15
4.1. Device Names ...........................................................................16
4.2. File Names and Blocklists ...........................................................17
4.3. The Root File System and GRUB ................................................17
5. GRUB Interfaces ...................................................................................18
5.1. Interfaces Load Order .................................................................19
6. GRUB Commands ................................................................................19
7. GRUB Menu Configuration File ..............................................................21
7.1. Configuration File Structure .........................................................21
7.2. Configuration File Directives .......................................................22
8. Changing Runlevels at Boot Time ..........................................................23
9. Additional Resources ............................................................................23
9.1. Installed Documentation .............................................................24
9.2. Useful Websites .........................................................................24
9.3. Related Books ...........................................................................24
3. File System Structure ....................................................................................25
1. Why Share a Common Structure? ..........................................................25
2. Overview of File System Hierarchy Standard (FHS) ................................25
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2.1. FHS Organization .......................................................................25
3. Special File Locations Under Red Hat Enterprise Linux ...........................30
4. The sysconfig Directory ...............................................................................31
1. Files in the /etc/sysconfig/ Directory ..................................................31
1.1. /etc/sysconfig/amd .................................................................33
1.2. /etc/sysconfig/apmd ...............................................................33
1.3. /etc/sysconfig/arpwatch ........................................................33
1.4. /etc/sysconfig/authconfig ....................................................33
1.5. /etc/sysconfig/autofs ...........................................................33
1.6. /etc/sysconfig/clock .............................................................34
1.7. /etc/sysconfig/desktop .........................................................35
1.8. /etc/sysconfig/devlabel ........................................................35
1.9. /etc/sysconfig/dhcpd .............................................................35
1.10. /etc/sysconfig/exim .............................................................36
1.11. /etc/sysconfig/firstboot ....................................................36
1.12. /etc/sysconfig/gpm ...............................................................36
1.13. /etc/sysconfig/harddisks ....................................................36
1.14. /etc/sysconfig/hwconf .........................................................37
1.15. /etc/sysconfig/i18n .............................................................37
1.16. /etc/sysconfig/init .............................................................37
1.17. /etc/sysconfig/ip6tables-config .......................................38
1.18. /etc/sysconfig/iptables-config .........................................39
1.19. /etc/sysconfig/irda .............................................................39
1.20. /etc/sysconfig/keyboard ......................................................40
1.21. /etc/sysconfig/kudzu ...........................................................40
1.22. /etc/sysconfig/mouse ...........................................................40
1.23. /etc/sysconfig/named ...........................................................41
1.24. /etc/sysconfig/netdump ........................................................42
1.25. /etc/sysconfig/network ........................................................42
1.26. /etc/sysconfig/ntpd .............................................................42
1.27. /etc/sysconfig/pcmcia .........................................................43
1.28. /etc/sysconfig/radvd ...........................................................43
1.29. /etc/sysconfig/rawdevices ..................................................43
1.30. /etc/sysconfig/samba ...........................................................43
1.31. /etc/sysconfig/selinux ........................................................44
1.32. /etc/sysconfig/sendmail ......................................................44
1.33. /etc/sysconfig/spamassassin ...............................................44
1.34. /etc/sysconfig/squid ...........................................................44
1.35. /etc/sysconfig/system-config-securitylevel ....................45
1.36. /etc/sysconfig/system-config-users ..................................45
1.37. /etc/sysconfig/system-logviewer .......................................45
1.38. /etc/sysconfig/tux ...............................................................45
1.39. /etc/sysconfig/vncservers ..................................................45
1.40. /etc/sysconfig/xinetd .........................................................46
2. Directories in the /etc/sysconfig/ Directory .........................................46
3. Additional Resources ............................................................................47
3.1. Installed Documentation .............................................................47
Red Hat Enterprise Linux 4.5.0
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5. The proc File System ....................................................................................49
1. A Virtual File System .............................................................................49
1.1. Viewing Virtual Files ...................................................................49
1.2. Changing Virtual Files ................................................................50
2. Top-level Files within the proc File System .............................................50
2.1. /proc/apm .................................................................................51
2.2. /proc/buddyinfo ......................................................................51
2.3. /proc/cmdline ..........................................................................52
2.4. /proc/cpuinfo ..........................................................................52
2.5. /proc/crypto ...........................................................................53
2.6. /proc/devices ..........................................................................53
2.7. /proc/dma .................................................................................54
2.8. /proc/execdomains ..................................................................54
2.9. /proc/fb ...................................................................................54
2.10. /proc/filesystems .................................................................54
2.11. /proc/interrupts ..................................................................55
2.12. /proc/iomem ...........................................................................55
2.13. /proc/ioports ........................................................................56
2.14. /proc/kcore ...........................................................................56
2.15. /proc/kmsg .............................................................................57
2.16. /proc/loadavg ........................................................................57
2.17. /proc/locks ...........................................................................57
2.18. /proc/mdstat ..........................................................................57
2.19. /proc/meminfo ........................................................................58
2.20. /proc/misc .............................................................................60
2.21. /proc/modules ........................................................................60
2.22. /proc/mounts ..........................................................................60
2.23. /proc/mtrr .............................................................................61
2.24. /proc/partitions ..................................................................61
2.25. /proc/pci ...............................................................................62
2.26. /proc/slabinfo ......................................................................62
2.27. /proc/stat .............................................................................64
2.28. /proc/swaps ...........................................................................64
2.29. /proc/sysrq-trigger .............................................................65
2.30. /proc/uptime ..........................................................................65
2.31. /proc/version ........................................................................65
3. Directories within /proc/ .......................................................................65
3.1. Process Directories ....................................................................65
3.2. /proc/bus/ ...............................................................................67
3.3. /proc/driver/ ..........................................................................68
3.4. /proc/fs ...................................................................................68
3.5. /proc/ide/ ...............................................................................69
3.6. /proc/irq/ ...............................................................................70
3.7. /proc/net/ ...............................................................................70
3.8. /proc/scsi/ .............................................................................71
3.9. /proc/sys/ ...............................................................................73
3.10. /proc/sysvipc/ ......................................................................85
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3.11. /proc/tty/ .............................................................................85
4. Using the sysctl Command ..................................................................86
5. Additional Resources ............................................................................87
5.1. Installed Documentation .............................................................87
5.2. Useful Websites .........................................................................87
6. Users and Groups .........................................................................................89
1. User and Group Management Tools .......................................................89
2. Standard Users .....................................................................................90
3. Standard Groups ..................................................................................91
4. User Private Groups ..............................................................................93
4.1. Group Directories .......................................................................94
5. Shadow Passwords ...............................................................................95
6. Additional Resources ............................................................................95
6.1. Installed Documentation .............................................................95
6.2. Related Books ...........................................................................96
7. The X Window System ..................................................................................99
1. The X11R6.8 Release ...........................................................................99
2. Desktop Environments and Window Managers .....................................100
2.1. Desktop Environments ..............................................................100
2.2. Window Managers ...................................................................101
3. X Server Configuration Files ................................................................101
3.1. xorg.conf ...............................................................................102
4. Fonts ..................................................................................................108
4.1. Fontconfig ................................................................................109
4.2. Core X Font System .................................................................110
5. Runlevels and X ..................................................................................112
5.1. Runlevel 3 ...............................................................................112
5.2. Runlevel 5 ...............................................................................113
6. Additional Resources ..........................................................................114
6.1. Installed Documentation ...........................................................114
6.2. Useful Websites .......................................................................114
6.3. Related Books .........................................................................115
II. Network Services Reference ................................................................................117
8. Network Interfaces ......................................................................................119
1. Network Configuration Files .................................................................119
2. Interface Configuration Files ................................................................120
2.1. Ethernet Interfaces ...................................................................120
2.2. IPsec Interfaces .......................................................................122
2.3. Channel Bonding Interfaces ......................................................124
2.4. Alias and Clone Files ................................................................125
2.5. Dialup Interfaces ......................................................................126
2.6. Other Interfaces .......................................................................127
3. Interface Control Scripts ......................................................................128
4. Network Function Files ........................................................................129
5. Additional Resources ..........................................................................130
5.1. Installed Documentation ...........................................................130
9. Network File System (NFS) .........................................................................131
Red Hat Enterprise Linux 4.5.0
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1. How It Works ......................................................................................131
1.1. Required Services ....................................................................132
1.2. NFS and portmap ....................................................................133
2. Starting and Stopping NFS ..................................................................134
3. NFS Server Configuration ....................................................................135
3.1. The /etc/exports Configuration File ........................................135
3.2. The exportfs Command ..........................................................138
4. NFS Client Configuration Files .............................................................139
4.1. /etc/fstab .............................................................................140
4.2. autofs ....................................................................................140
4.3. Common NFS Mount Options ...................................................142
5. Securing NFS .....................................................................................143
5.1. Host Access .............................................................................143
5.2. File Permissions .......................................................................145
6. Additional Resources ..........................................................................145
6.1. Installed Documentation ...........................................................145
6.2. Useful Websites .......................................................................146
6.3. Related Books .........................................................................146
10. Apache HTTP Server ................................................................................147
1. Apache HTTP Server 2.0 .....................................................................147
1.1. Features of Apache HTTP Server 2.0 ........................................147
1.2. Packaging Changes in Apache HTTP Server 2.0 ........................148
1.3. File System Changes in Apache HTTP Server 2.0 ......................148
2. Migrating Apache HTTP Server 1.3 Configuration Files .........................149
2.1. Global Environment Configuration .............................................150
2.2. Main Server Configuration ........................................................153
2.3. Virtual Host Configuration .........................................................155
2.4. Modules and Apache HTTP Server 2.0 ......................................155
3. After Installation ..................................................................................161
4. Starting and Stopping httpd ................................................................162
5. Configuration Directives in httpd.conf ................................................163
5.1. General Configuration Tips .......................................................163
5.2. ServerRoot .............................................................................164
5.3. PidFile ..................................................................................164
5.4. Timeout ..................................................................................164
5.5. KeepAlive ...............................................................................164
5.6. MaxKeepAliveRequests ...........................................................164
5.7. KeepAliveTimeout ..................................................................165
5.8. IfModule .................................................................................165
5.9. MPM Specific Server-Pool Directives .........................................165
5.10. Listen ..................................................................................166
5.11. Include .................................................................................167
5.12. LoadModule ...........................................................................167
5.13. ExtendedStatus ....................................................................167
5.14. IfDefine ...............................................................................167
5.15. SuexecUserGroup ..................................................................167
5.16. User ......................................................................................168
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5.17. Group ....................................................................................168
5.18. ServerAdmin .........................................................................168
5.19. ServerName ...........................................................................168
5.20. UseCanonicalName ................................................................169
5.21. DocumentRoot ........................................................................169
5.22. Directory .............................................................................169
5.23. Options .................................................................................170
5.24. AllowOverride ......................................................................170
5.25. Order ....................................................................................171
5.26. Allow ....................................................................................171
5.27. Deny ......................................................................................171
5.28. UserDir .................................................................................171
5.29. DirectoryIndex ....................................................................171
5.30. AccessFileName ....................................................................172
5.31. CacheNegotiatedDocs ...........................................................172
5.32. TypesConfig .........................................................................172
5.33. DefaultType .........................................................................172
5.34. HostnameLookups ..................................................................172
5.35. ErrorLog ...............................................................................173
5.36. LogLevel ...............................................................................173
5.37. LogFormat .............................................................................173
5.38. CustomLog .............................................................................174
5.39. ServerSignature ..................................................................174
5.40. Alias ....................................................................................174
5.41. ScriptAlias .........................................................................174
5.42. Redirect ...............................................................................174
5.43. IndexOptions ........................................................................175
5.44. AddIconByEncoding ...............................................................175
5.45. AddIconByType ......................................................................175
5.46. AddIcon .................................................................................175
5.47. DefaultIcon .........................................................................176
5.48. AddDescription ....................................................................176
5.49. ReadmeName ...........................................................................176
5.50. HeaderName ...........................................................................176
5.51. IndexIgnore .........................................................................176
5.52. AddEncoding .........................................................................176
5.53. AddLanguage .........................................................................176
5.54. LanguagePriority ................................................................176
5.55. AddType .................................................................................177
5.56. AddHandler ...........................................................................177
5.57. Action ..................................................................................177
5.58. ErrorDocument ......................................................................177
5.59. BrowserMatch ........................................................................177
5.60. Location ...............................................................................178
5.61. ProxyRequests ......................................................................178
5.62. Proxy ....................................................................................178
5.63. Cache Directives ....................................................................178
Red Hat Enterprise Linux 4.5.0
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