Ubuntu Server Guide - Del Mar College

1 Ubuntu Server GuideUbuntu Server GuideCopyright 2010 Canonical Ltd. and members of the Ubuntu Documentation Project3 AbstractWelcome to the Ubuntu Server Guide ! It contains information on how to install and configure various serverapplications on your Ubuntu system to fit your needs. It is a step-by-step, task-oriented Guide for configuringand customizing your and LicenseThis document is maintained by the Ubuntu documentation team ( ). For a list of contributors,see the contributors page1 This document is made available under the Creative Commons ShareAlike License (CC-BY-SA).You are free to modify, extend, and improve the Ubuntu documentation source code under the terms of this license. All derivative worksmust be released under this documentation is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warrantyof MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE AS DESCRIBED IN THE copy of the license is available here: Creative Commons ShareAlike ~ Ubuntu -core-doc1.

2 /../libs/ /usr/share/ Ubuntu -docs/libs/ of Contents1. Introduction .. 11. Support .. 22. Installation .. 31. Preparing to Install .. 42. Installing from CD .. 63. Upgrading .. 94. Advanced Installation .. 103. Package Management .. 171. Introduction .. 182. dpkg .. 193. Apt-Get .. 204. Aptitude .. 225. Automatic Updates .. 246. Configuration .. 267. References .. 284. Networking .. 291. Network Configuration .. 302. TCP/IP .. 383. Dynamic Host Configuration Protocol (DHCP) .. 424. Time Synchronisation with NTP .. 455. Remote Administration .. 471. OpenSSH Server .. 482. Puppet .. 516. Network Authentication .. 541. OpenLDAP Server .. 552. Samba and LDAP.

3 743. Kerberos .. 804. Kerberos and LDAP .. 877. Domain Name Service (DNS) .. 931. Installation .. 942. Configuration .. 953. Troubleshooting .. 1004. References .. 1048. Security .. 1051. User Management .. 1062. Console Security .. 1123. Firewall .. 1134. AppArmor .. 1205. Certificates .. 1246. eCryptfs .. 129 Ubuntu Server Guideiv9. Monitoring .. 1311. Overview .. 1322. Nagios .. 1333. Munin .. 13710. Web Servers .. 1391. HTTPD - Apache2 Web Server .. 1402. PHP5 - Scripting Language .. 1473. Squid - Proxy Server .. 1494. Ruby on Rails .. 1515. Apache Tomcat .. 15311. Databases .. 1571. MySQL .. 1582. PostgreSQL .. 16012. LAMP Applications.

4 1621. Overview .. 1632. Moin Moin .. 1643. MediaWiki .. 1664. phpMyAdmin .. 16813. File Servers .. 1701. FTP Server .. 1712. Network File System (NFS) .. 1753. CUPS - Print Server .. 17714. Email Services .. 1801. Postfix .. 1812. Exim4 .. 1883. Dovecot Server .. 1914. Mailman .. 1935. Mail Filtering .. 19915. Chat Applications .. 2061. Overview .. 2072. IRC Server .. 2083. Jabber Instant Messaging Server .. 21016. Version Control System .. 2121. Bazaar .. 2132. Subversion .. 2143. CVS Server .. 2194. References .. 22117. Windows Networking .. 2221. Introduction .. 2232. Samba File Server .. 2243. Samba Print Server .. 2274. Securing a Samba File and Print Server .

5 229 Ubuntu Server Guidev5. Samba as a Domain Controller .. 2336. Samba Active Directory Integration .. 2377. Likewise Open .. 23918. Backups .. 2431. Shell Scripts .. 2442. Archive Rotation .. 2483. Bacula .. 25119. Virtualization .. 2561. libvirt .. 2572. JeOS and vmbuilder .. 2623. UEC .. 27120. Clustering .. 2841. DRBD .. 28521. VPN .. 2881. OpenVPN .. 28922. Other Useful Applications .. 2931. pam_motd .. 2942. etckeeper .. 2963. Byobu .. 2984. References .. 300A. Appendix .. 3011. Reporting Bugs in Ubuntu Server Edition .. 302viList of Recommended Minimum Requirements .. Access Methods .. UEC Front End Requirements .. UEC Node Requirements .. 2731 Chapter 1.

6 IntroductionWelcome to the Ubuntu Server Guide !Here you can find information on how to install and configure various Server applications. It is a step-by-step, task-oriented Guide for configuring and customizing your Guide assumes you have a basic understanding of your Ubuntu system. Some installation detailsare covered in Chapter 2, Installation [p. 3], but if you need detailed instructions installingUbuntu please refer to the Ubuntu Installation HTML version of the manual is available online at the Ubuntu Documentation website2. TheHTML files are also available in the Ubuntu -serverguide package. See Chapter 3, PackageManagement [p. 17] for details on installing you choose to install the Ubuntu -serverguide you can view this document from a console by:w3m /usr/share/ Ubuntu -serverguide/html/ you are using a localized version of Ubuntu , replace C with your language localization( en_GB).

7 1 SupportThere are a couple of different ways that Ubuntu Server Edition is supported, commercial supportand community support. The main commercial support (and development funding) is available fromCanonical Ltd. They supply reasonably priced support contracts on a per desktop or per Server more information see the Canonical Services3 support is also provided by dedicated individuals, and companies, that wish to makeUbuntu the best distribution possible. Support is provided through multiple mailing lists, IRCchannels, forums, blogs, wikis, etc. The large amount of information available can be overwhelming,but a good search engine query can usually provide an answer to your questions. See the UbuntuSupport4 page for more 2. InstallationThis chapter provides a quick overview of installing Ubuntu Server Edition.

8 For more detailedinstructions, please refer to the Ubuntu Installation Preparing to InstallThis section explains various aspects to consider before starting the System RequirementsUbuntu Server Edition supports two (2) major architectures: Intel x86 and AMD64. The tablebelow lists recommended hardware specifications. Depending on your needs, you might manage withless than this. However, most users risk being frustrated if they ignore these Recommended Minimum RequirementsHard Drive SpaceInstall TypeRAMBaseSystemAll Tasks InstalledServer128 megabytes500megabytes1 gigabyteThe Server Edition provides a common base for all sorts of Server applications. It is a minimalistdesign providing a platform for the desired services, such as file/print services, web hosting, emailhosting, requirements for UEC are slightly different for Front End requirements see Section , Front End Requirements [p.]

9 271] and for UEC Node requirements see Section , NodeRequirements [p. 272]. Server and Desktop DifferencesThere are a few differences between the Ubuntu Server Edition and the Ubuntu Desktop Edition. Itshould be noted that both editions use the same apt repositories. Making it just as easy to install aserver application on the Desktop Edition as it is on the Server differences between the two editions are the lack of an X window environment in the ServerEdition, the installation process, and different Kernel Kernel Differences: The Server Edition uses the Deadline I/O scheduler instead of the CFQ scheduler used by theDesktop Edition. Preemption is turned off in the Server Edition. The timer interrupt is 100 Hz in the Server Edition and 250 Hz in the Desktop running a 64-bit version of Ubuntu on 64-bit processors you are not limited bymemory addressing see all kernel configuration options you can look through / Also,Linux Kernel in a Nutshell2 is a great resource on the options Backing Up Before installing Ubuntu Server Edition you should make sure all data on the system is backed Chapter 18, Backups [p.

10 243] for backup this is not the first time an operating system has been installed on your computer, it is likely youwill need to re-partition your disk to make room for time you partition your disk, you should be prepared to lose everything on the disk should youmake a mistake or something goes wrong during partitioning. The programs used in installation arequite reliable, most have seen years of use, but they also perform destructive Installing from CDThe basic steps to install Ubuntu Server Edition from CD are the same for installing any operatingsystem from CD. Unlike the Desktop Edition the Server Edition does not include a graphicalinstallation program. Instead the Server Edition uses a console menu based process. First, download and burn the appropriate ISO file from the Ubuntu web site3. Boot the system from the CD-ROM drive.