installing linux software

8/6/2019 Installing Linux Software

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Installing Linux Software

IntroductionYou'll frequently need to install additional software on your Linux server that you didn't think you'd

need when you first installed the operating system. This could be because of new business requirements

for additional packages or the need to install new administrative tools to make your job easier.

When Linux developers create their software they typically bundle all the executable and data files into

a single file that is often called a "package" file. Package files have different formats and contain

different control files that determine where the rest of the files should be placed, the permissions they

should have and a list of prerequisite packages that are required for the package to function correctly.

Some of this information may also be stored in a database on your system by the package management

software used to install the software and is used to speed up some of the administrative functions of thepackage manager.

Redhat, Centos and Fedora Linux software is primarily available in RedHat Package Manager (RPM)

files. Regular RPM package files are used for installations in which the kernel, or master program,

hasn't been customized in any way. This is the usual scenario for most departmental servers. Source

RPMs are used when the kernel has been customized to add or drop support selectively for various

devices or features for the sake of performance or functionality. The procedure for installing source

RPMs involves recompiling source code to fit the needs of these kernel customizations. This makes life

easier for the software developer who wrote the package as he or she now has only to create a single

package to support all types of customizations. Both package types use standardized commands for

installing the software contained inside making RPMs relatively easy to use.Debian and Ubuntu versions of Linux use the Debian Package format in which the filenames all end

with ".deb". It is for this reason that they are frequently called DEB files.

Software developers who want to use a universally recognizable file format across all flavors of Linux

also will make their products available as TAR packages. TAR packages are generally more difficult to

work with than RPM packages because the archived files within them may or may not need to be

compiled and the commands to install the software may vary from package to package. Instructions are

usually contained within a file inside the TAR package to help guide the installation.

The Perl programming language is often used by Linux software developers to create their programs.

Perl relies on the presence of certain libraries, or "modules", to work correctly and many Linux

distributions install Perl with only the most commonly used ones. There will be times when you will be

required to install additional prerequisite Perl modules prior to the installation of your packages.

Knowledge of how to install Perl modules is a valuable component of a Linux systems administrators'

skill set.

This chapter focuses on the RPM and DEB formats, which are used by a majority of installed

distributions. There are smaller sections on TAR packages and Perl modules near the end to cover these

less frequently used, but important software installation tools.


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Where to Get Commonly Used PackagesThere are three commonly used sources for packages; distribution CDs; packages manually downloaded

via a browser, File Transfer Protocol (FTP) client, or the wget utility; and automated downloads. Each

of these methods is introduced here, but is covered in greater detail in sections to follow.

Packages on Your Installation CDs

Installing from your distribution CDs is usually easier than having to download files from a remote

Web site, but they are never up to date for very long. We discuss using this method in more detail later.

Manually Downloaded Packages

The two most common ways of getting packages are by manually using FTP or a Web browser. Table 6

1 lists some common download sites that can be used. Remember to match the RPM to the distribution

and version of Linux your system is running.

Table 6 1 Popular Package Download Sites

Distribution Location

Redhat

http://www.redhat.com/

http://www.rpmfind.net/

Fedora

ftp://download.fedora.redhat.com/pub/fedora/linux/core/

http://download.fedora.redhat.com/pub/fedora/linux/core/http://www.rpmfind.net/

Debian http://packages.debian.org

Ubuntu http://packages.ubuntu.com

Note: With Fedora you can also download packages from the download.fedora.redhat.com site. Start

your search in the /pub/fedora/linux/core/ directory and move down the directory tree. If you're new to

FTP, don't worry, it's explained later.

Automated Package Download

The disadvantage of manual downloads is that the packages often won't install unless certain

prerequisite packages have been installed beforehand. This can lead to the download and installation of

several packages which can become tedious.

All the major Linux distributions have automated download and update utilities. For example, Fedora

uses yum and Ubuntu and Debian use apt. These are all covered in greater detail in sections to follow.
http://www.redhat.com/http://www.rpmfind.net/ftp://download.fedora.redhat.com/pub/fedora/linux/core/http://download.fedora.redhat.com/pub/fedora/linux/core/http://www.rpmfind.net/http://packages.debian.org/http://packages.ubuntu.com/http://www.redhat.com/http://www.rpmfind.net/ftp://download.fedora.redhat.com/pub/fedora/linux/core/http://download.fedora.redhat.com/pub/fedora/linux/core/http://www.rpmfind.net/http://packages.debian.org/http://packages.ubuntu.com/


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How to Download SoftwareOne of the most universally performed tasks by Linux systems administrators is the downloading of

software. It is usually very simple to do and the most commonly used methods are covered in this

section.

Getting Software Using Web Based FTP

There are numerous Web sites that provide links to software you can download. The methodology to get

the software is usually the same for all:

Browse the desired Web site until you find the link to the software package you need.

Click on the link for the desired software package.

Save the file to your hard drive

Some web browsers, such as Firefox, will automatically download the file to your desktop, but where is

the desktop? In Linux, your desktop is usually a sub directory named Desktop located in your home or

~ directory. Here we see that the root user's desktop already contains a downloaded RPM file.

[root@bigboy tmp]# cd ~/Desktop/[root@bigboy Desktop]# lsElectricFence-2.2.2-20.2.i386.rpm[root@bigboy Desktop]# pwd/root/Desktop[root@bigboy Desktop]#

Getting RPMs Using Command Line Anonymous FTP

The Web based method above transparently uses anonymous File Transfer Protocol (FTP). AnonymousFTP allows you to log in and download files from a FTP server using the username anonymous or the

shorter username ftp and a password that matches your e mail address. This way anyone can access the

data. Let's illustrate this with an example of using anonymous FTP to download the SSH package from

download.fedora.redhat.com:

1) First we issue the FTP command targeting download.fedora.redhat.com at the command line.

[root@bigboy tmp]# ftp download.fedora.redhat.comTrying 66.187.232.35...Connected to download.fedora.redhat.com (66.187.232.35).220 Fedora FTP server ready. All transfers are logged.Name (download.fedora.redhat.com:root): anonymous

331 Please specify the password.Password:230 Login successful. Have fun.Using binary mode to transfer files.ftp> pwd257 "/"ftp> ls227 Entering Passive Mode (66,187,232,35,57,155)150 Here comes the directory listing.drwxr-xr-x 3 ftp ftp 4096 Oct 29 15:59 pub226 Directory send OK.


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ftp>

2) After we've logged in, we can use the help command to see what options we have at our disposal.

ftp> helpCommands may be abbreviated. Commands are:

! cr mdir proxy send

$ delete mget sendport siteaccount debug mkdir put sizeappend dir mls pwd statusascii disconnect mode quit structbell form modtime quote systembinary get mput recv suniquebye glob newer reget tenexcase hash nmap rstatus traceccc help nlist rhelp typecd idle ntrans rename usercdup image open reset umaskchmod lcd passive restart verboseclear ls private rmdir ?

close macdef prompt runiquecprotect mdelete protect safeftp>

The commands you'll most likely use are listed in Table 6 2:

Table 6 2 FTP Commands

Command Description

binary Copy files in binary mode

cd Change directory on the FTP server

dir List the names of the files in the current remote directory

exit Bye bye

get Get a file from the FTP server

lcd Change the directory on the local machine

ls Same as dir

mget Same as get, but you can use wildcards like "*"

mput Same as put, but you can use wildcards like "*"

passive Make the file transfer passive mode

put Put a file from the local machine onto the FTP server


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pwd Give the directory name on the local machine

3) By using the Web browsing feature on the Web site ahead of time, I know that the Fedora Core 2

RPMs are located in the pub/fedora/linux/core/2/i386/os/Fedora/RPMS/ directory and will use the cd

command to change my directory to there. We can use the ls command to get a listing of files in this

directory.

ftp> cd pub/fedora/linux/core/2/i386/os/Fedora/RPMS/250 Directory successfully changed.ftp> ls open*227 Entering Passive Mode (66,187,232,35,58,3)150 Here comes the directory listing.......-rw-r--r-- ... ... 184281 Oct 28 23:29 openssh-3.6.1p2-34.i386.rpm......226 Directory send OK.ftp>

4) Next we get the file we need and place it in the local directory /usr/rpm. The hash command willprint "#" hash signs on the screen during the download.

ftp> hashHash mark printing on (1024 bytes/hash mark).ftp> lcd /usr/rpmLocal directory now /usr/rpmftp> get openssh-3.6.1p2-34.i386.rpmlocal: openssh-3.6.1p2-34.i386.rpm remote: openssh-3.6.1p2-34.i386.rpm227 Entering Passive Mode (66,187,232,35,58,25)150 Opening BINARY mode data connection for openssh-3.6.1p2-34.i386.rpm (184281bytes).#################################################################################

##################################################################################################226 File send OK.184281 bytes received in 3.41 secs (53 Kbytes/sec)ftp>

Note: You can also use wildcards to download the RPMs you need using the mget command. You'll be

prompted for each of the matching RPM files. In the next example, we just aborted this download by

typing n.

ftp> mget openssh-3.6*mget openssh-3.6.1p2-34.i386.rpm? nftp>

5) Finally we use the exit command to leave FTP.

ftp> exit221 Goodbye.root@bigboy tmp]#


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Getting Software Using wget

The wget command can be used to download files quickly when you already know the URL at which

the RPM is located. This is especially convenient if you are logged into your Linux box from another

machine running a Web browser. You can browse the download site for the RPM you need, right click

on the desired link and select copy shortcut (Windows) or Copy Link Location (Linux). After you have

done this, you can then select your SSH/telnet/Linux Terminal login window and type in the commandwget URL. Here is an example downloading a DHCP update from Fedora.

[root@bigboy tmp]# wgethttp://linux.stanford.edu/pub/mirrors/fedora/linux/core/2/i386/os/Fedora/RPMS/dhcp-3.0pl2-6.16.i386.rpm--17:38:36--ftp://linux.stanford.edu/pub/mirrors/fedora/linux/core/2/i386/os/Fedora/RPMS/dhcp-3.0pl2-6.16.i386.rpm

=> `dhcp-3.0pl2-6.16.i386.rpm.5'Resolving linux.stanford.edu... done.Connecting to linux.stanford.edu[171.66.2.18]:21... connected.Logging in as anonymous ... Logged in!

==> SYST ... done. ==> PWD ... done.==> TYPE I ... done. ==> CWD /pub/mirrors/fedora/linux/core/2/i386/os/Fedora/RPMS... done.==> PASV ... done. ==> RETR dhcp-3.0pl2-6.16.i386.rpm ... done.Length: 529,890 (unauthoritative)100%[===============================>] 529,890 889.12K/s ETA 00:0017:38:36 (889.12 KB/s) - `dhcp-3.0pl2-6.16.i386.rpm.5' saved [529890][root@bigboy tmp]#

Installing Software From RPM FilesThe Fedora, Redhat and Centos versions of Linux rely heavily upon the use of software packages in the

RPM format. This section covers some of the most important topics required for you to master their

use.

How To Install RPMs Manually

There are generally two ways to install RPM files manually. The first method is by using a filepreviously downloaded to your hard drive, and the other is to install the RPM from some sort of

removable media such as a CD ROM drive.

Using Downloaded Files

Download the RPMs (which usually have a file extension ending with .rpm) into a temporary directory,

such as /tmp. The next step is to issue the rpm Uvh command to install the package.
http://linux.stanford.edu/pub/mirrors/fedora/linux/core/2/i386/os/Fedora/RPMS/dhcp-3.0pl2-6.16.i386.rpmhttp://linux.stanford.edu/pub/mirrors/fedora/linux/core/2/i386/os/Fedora/RPMS/dhcp-3.0pl2-6.16.i386.rpmftp://linux.stanford.edu/pub/mirrors/fedora/linux/core/2/i386/os/Fedora/RPMS/dhcp-3.0pl2-6.16.i386.rpmftp://linux.stanford.edu/pub/mirrors/fedora/linux/core/2/i386/os/Fedora/RPMS/dhcp-3.0pl2-6.16.i386.rpmhttp://linux.stanford.edu/pub/mirrors/fedora/linux/core/2/i386/os/Fedora/RPMS/dhcp-3.0pl2-6.16.i386.rpmhttp://linux.stanford.edu/pub/mirrors/fedora/linux/core/2/i386/os/Fedora/RPMS/dhcp-3.0pl2-6.16.i386.rpmftp://linux.stanford.edu/pub/mirrors/fedora/linux/core/2/i386/os/Fedora/RPMS/dhcp-3.0pl2-6.16.i386.rpmftp://linux.stanford.edu/pub/mirrors/fedora/linux/core/2/i386/os/Fedora/RPMS/dhcp-3.0pl2-6.16.i386.rpm


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The U qualifier is used for updating an RPM to the latest version, the h qualifier gives a list of hash #

characters during the installation and the v qualifier prints verbose status messages while the command

is run. Here is an example of a typical RPM installation command to install the MySQL server package:

[root@bigboy tmp]# rpm -Uvh mysql-server-3.23.58-9.i386.rpmPreparing... ####################### [100%]1:mysql-server ####################### [100%]

[root@bigboy tmp]#

Using CD ROMs

The underlying steps to install RPMs from CDs are similar to those used when installing from your

hard disk. The main difference is that you have to access your CD ROM drive by mounting it first to

the mnt/cdrom directory. Your RPMs will then be located in the CD ROM's Fedora/RPMs subdirectory.

The procedure is as follows:

1) Insert the CD ROM, check the files in the /mnt/cdrom/Fedora/RPMS directory and then install the

RPM.

[root@bigboy tmp]# mount /mnt/cdrom[root@bigboy tmp]# cd /mnt/cdrom/Fedora/RPMS[root@bigboy RPMS]# ls filename*filename.rpm[root@bigboy RPMS]# rpm -Uvh filename.rpmPreparing... ####################### [100%]1: filename ####################### [100%]

[root@bigboy RPMS]#

2) When finished, eject the CD ROM

[root@bigboy RPMS]# cd /tmp[root@bigboy tmp]# eject cdrom[root@bigboy tmp]#

Note: You can use the rpm command's aid switch to make it search the CD ROM for any other RPM

dependencies and install them automatically.

How to Install Source RPMs

Sometimes the packages you want to install need to be compiled in order to match your kernel version.

This requires you to use source RPM files:

Download the source RPMs or locate them on your CD collection. They usually have a file

extension ending with (.src.rpm)

Run the following commands as root:

Compiling and installing source RPMs with Fedora can be done simply with the rpmbuild command

[root@bigboy tmp]# rpmbuild --rebuild filename.src.rpm


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Here is an example in which we install the tacacs plus package.

[root@bigboy rpm]# rpmbuild --rebuild tac_plus-4.0.3-2.src.rpmInstalling tac_plus-4.0.3-2.src.rpmExecuting(%prep): /bin/sh -e /var/tmp/rpm-tmp.61594+ umask 022+ cd /usr/src/redhat/BUILD+ cd /usr/src/redhat/BUILD

+ rm -rf tac_plus-4.0.3+ /usr/bin/gzip -dc /usr/src/redhat/SOURCES/tac_plus-4.0.3.tgz+ tar -xvvf -.........+ umask 022+ cd /usr/src/redhat/BUILD+ rm -rf tac_plus-4.0.3+ exit 0[root@bigboy rpm]#

The compiled RPM file can now be found in one of the architecture subdirectories under

/usr/src/redhat/RPMS directory. For example, if you compiled an i386 architecture version of the RPM

it will placed in the i386 subdirectory.

You will then have to install the compiled RPMs found in their respective subdirectories as you

normally would.

RPM Installation Errors

Sometimes the installation of RPM software doesn't go according to plan and you need to take

corrective actions. This section shows you how to recover from some of the most common errors you'llencounter.

Failed Dependencies

Sometimes RPM installations will fail giving Failed dependencies errors which really mean that a

prerequisite RPM needs to be installed. In the next example we're attempting to install the MySQL

database server application, which fails because the mysql MySQL client RPM, on which it depends,

needs to be installed beforehand:

[root@bigboy tmp]# rpm -Uvh mysql-server-3.23.58-9.i386.rpmerror: Failed dependencies:

libmysqlclient.so.10 is needed by mysql-server-3.23.58-9mysql = 3.23.58 is needed by mysql-server-3.23.58-9

[root@bigboy tmp]#

Installing the MySQL client also fails because it requires the perl DBD MySQL package.

[root@bigboy tmp]# rpm -Uvh mysql-3.23.58-9.i386.rpmerror: Failed dependencies:

perl-DBD-MySQL is needed by mysql-3.23.58-9


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[root@bigboy tmp]# rpm -Uvh perl-DBD-MySQL-2.9003-4.i386.rpmerror: Failed dependencies:

libmysqlclient.so.10 is needed by perl-DBD-MySQL-2.9003-4[root@bigboy tmp]#

Strangely enough, the installation of the perl DBD MySQL package fails because it needs the mysql

client package. To get around this problem you can run the rpm command with the nodeps option to

disable dependency checks. In the next example we install the MySQL client ignoring dependencies,followed by successful installation of perl DBD MySQL and mysql server.

[root@bigboy tmp]# rpm -Uvh --nodeps mysql-3.23.58-9.i386.rpmPreparing... ####################### [100%]

1:mysql ####################### [100%][root@bigboy tmp]# rpm -Uvh perl-DBD-MySQL-2.9003-4.i386.rpmPreparing... ####################### [100%]

1:perl-DBD-MySQL ####################### [100%][root@bigboy tmp]# rpm -Uvh mysql-server-3.23.58-9.i386.rpmPreparing... ####################### [100%]

1:mysql-server ####################### [100%][root@bigboy tmp]#

Note: If all the installation RPMs are located in the same directory, the rpm command can

automatically install all the prerequisite RPMs using the aid option. One of the advantages of using

the yum facility is that you don't have to worry about this dependency process as much because the

dependency RPMs are always downloaded and installed automatically also.

Signature Keys

Fedora digitally signs all its RPM files, so it's best to import their public encryption key beforehand so

that the RPM installation program will be able to verify the validity of the RPM file.

This is usually done automatically in newer versions of Fedora, but will need to be done manually inlegacy versions. The manual method uses the rpm command as seen in the next example, but locate the

key files first as their locations can vary between Fedora distributions. It is a good idea to import both

the RedHat and Fedora keys:

[root@bigboy tmp]# locate RPM-GPG-KEY/usr/share/rhn/RPM-GPG-KEY/usr/share/rhn/RPM-GPG-KEY-fedora[root@bigboy tmp]# rpm --import /usr/share/rhn/RPM-GPG-KEY[root@bigboy tmp]# rpm --import /usr/share/rhn/RPM-GPG-KEY-fedora[root@bigboy tmp]#

If you don't install the keys you'll get a DSA signature warning that alerts you to the fact that the RPM

file might be bogus:

[root@bigboy tmp]# rpm -Uvh dhcp-3.0pl2-6.16.i386.rpmwarning: dhcp-3.0pl2-6.16.i386.rpm: V3 DSA signature: NOKEY, key ID 4f2a6fd2Preparing... #################################### [100%]

1:dhcp #################################### [100%][root@bigboy tmp]#


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It is always good to install the key files. If they are not there, the RPMs will install with only a warning

message. If the RPM's digital signature doesn't match that in the key file, the rpm installation program

also alerts you and fails to install the RPM package at all:

[root@bigboy tmp]# rpm -Uvh dhcp-3.0pl2-6.16.i386.rpmerror: dhcp-3.0pl2-6.16.i386.rpm: V3 DSA signature: BAD, key ID 4f2a6fd2error: dhcp-3.0pl2-6.16.i386.rpm cannot be installed[root@bigboy tmp]#

Signatures are therefore useful because they help protect you against tampered and otherwise corrupted

RPMs being installed.

How to List Installed RPMs

The rpm qa command will list all the packages installed on your system

[root@bigboy tmp]# rpm -qaperl-Storable-1.0.14-15smpeg-gtv-0.4.4-9

e2fsprogs-1.27-9libstdc++-3.2-7audiofile-0.2.3-3.........[root@bigboy tmp]#

You can also pipe the output of this command through the grep command if you are interested in only a

specific package. In this example we are looking for all packages containing the string ssh in the name,

regardless of case ( i means ignore case)

[root@bigboy tmp]# rpm -qa | grep -i ssh

openssh-server-3.4p1-2openssh-clients-3.4p1-2openssh-askpass-gnome-3.4p1-2openssh-3.4p1-2openssh-askpass-3.4p1-2[root@bigboy tmp]#

Note: You could use the rpm q package name command to find an installed package because it is

much faster than using grep and the qa switch, but you have to have an exact package match. If you are

not sure of the package name and its capitalization, the latter method is probably more suitable.

Listing Files Associated with RPMs

Sometimes you'll find yourself installing software that terminates with an error requesting the presence

of a particular file. In many cases the installation program doesn't state the RPM package in which the

file can be found. It is therefore important to be able to determine the origin of certain files, by listing

the contents for RPMs in which you suspect the files might reside.


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Listing Files for Already Installed RPMs

This can be useful if you have to duplicate a working server that is already in a production environment.

Sometimes the installation of an application fails on the new server due to the lack of a file that resides

on the old one. In this case you need to know which RPM on the old server contains the file.

You can use the ql qualifier to list all the files associated with an installed RPM. In this example we

test to make sure that the NTP package is installed using the q qualifier, and then we use the qlqualifier to get the file listing.

[root@bigboy tmp]# rpm -q ntpntp-4.1.2-0.rc1.2[root@bigboy tmp]# rpm -ql ntp/etc/ntp/etc/ntp.conf/etc/ntp/drift/etc/ntp/keys.........

/usr/share/doc/ntp-4.1.2/rdebug.htm/usr/share/doc/ntp-4.1.2/refclock.htm/usr/share/doc/ntp-4.1.2/release.htm/usr/share/doc/ntp-4.1.2/tickadj.htm[root@bigboy tmp]#

Listing Files in RPM Files

Sometimes you make a guess and download what you think is the RPM with the missing file. You can

use the qpl qualifier to list all the files in an RPM archive to make sure before installing it:

[root@bigboy updates]# rpm -qpl dhcp-3.0pl1-23.i386.rpm/etc/rc.d/init.d/dhcpd/etc/rc.d/init.d/dhcrelay/etc/sysconfig/dhcpd/etc/sysconfig/dhcrelay........./usr/share/man/man8/dhcrelay.8.gz/var/lib/dhcp/var/lib/dhcp/dhcpd.leases[root@bigboy updates]#

Listing the RPM to Which a File Belongs

You might need to know the RPM that was used to install a particular file. This is useful when you have

a suspicion about the function of a file but are not entirely sure. For example, the MySQL RPM uses

the /etc/my.cnf file as its configuration file, not a file named /etc/mysql.conf as you'd normally expect.

The following example confirms the origin of the /etc/my.cnf file.


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[root@zippy tmp]# rpm -qf /etc/my.cnfmysql-3.23.58-9[root@zippy tmp]#

Uninstalling RPMsThe rpm e command will erase an installed package. The package name given must match that listed in

the rpm qa command because the version of the package is important.

[root@bigboy tmp]# rpm -e package-name

Which RPMs Will Start Up At Boot Time?

The best way to view and configure which RPMs will start at boot time is by using the chkconfig

command with the list switch. A more detailed explanation will be provided in Chapter 7, " The LinuxBoot Process", which covers the Linux boot process.

Automatic Updates with yum

The yum automatic RPM update program comes as a standard feature of Fedora Core. It has a number

of valuable features:

You can configure the URLs of download sites containing the RPM repositories you need. This

provides the added advantage of you choosing the most reliable sites in your part of the globe.

yum makes multiple attempts to download RPMs before failing.

yum automatically figures out not only the RPMs packages that need updating, but also all thesupporting RPMs. It then installs them all.

Note: Updating packages could cause programs written by you to stop functioning especially if they

rely on the older version's features or syntax.

Configuring yum

The configuration parameters that affect all packages and all yum server URLs are stored in the [main]

section of the /etc/yum.conf file. You generally don't need to edit this file, but it can be useful in listing

packages that you don't want yum to update.

## File: /etc/yum.conf#

[main]exclude=kernel perl

In this example the kernel and perl packages are excluded.
http://www.linuxhomenetworking.com/wiki/index.php/Quick_HOWTO_:_Ch07_:_The_Linux_Boot_Processhttp://www.linuxhomenetworking.com/wiki/index.php/Quick_HOWTO_:_Ch07_:_The_Linux_Boot_Processhttp://www.linuxhomenetworking.com/wiki/index.php/Quick_HOWTO_:_Ch07_:_The_Linux_Boot_Processhttp://www.linuxhomenetworking.com/wiki/index.php/Quick_HOWTO_:_Ch07_:_The_Linux_Boot_Process


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Configuring /etc/yum.repos.d Repository Files

The /etc/yum.repos.d directory has files defining where yum should look on the Internet to find the

latest Linux updates. For most common tasks you wont need to modify these files at all. If you want to

know how these files affect your system, then continue reading! The configurations for each RPM

repository are located in individual configuration files with the .repo file extension. This directory will

be populated with files for your Linux distribution's most important repositories. You can also add your

own custom files for repositories containing non standard RPM packages. These files will have the

following format:

[repositoryid]name=Some name for this repositorybaseurl=url://path/to/repository/

The [repositoryid] is an identifier that is unique to all files in the directory and can only be one word

long and is often given a name that reflects the function of the repository. For example, you may have a

fedora updates.repo file that contains a [updates], and [updates source] sections that refer to URLs for

updates of regular RPMs and source RPMs. You can create your own repository files using popularrepository sites. The easiest way to determine the exact URLs to use as the baseurl parameter is to go to

thehttp://fedora.redhat.com/download/mirrors.html Web site to get a listing of alternative download

sites. Browse the listed sites to find the correct locations of the RPM files in the /updates or /fedora

version URL branches. Make sure that baseurl points to a URL with a /repodata sub directory beneath

it as this sub directory contains files with instructions for yum to use in doing its updates. Be careful,

this sub directory can be located within the RPM directory or one level above them. Also remember to

make the [repositoryid] in your .repo file unique to all other files.

Note: yum accepts the use of variables in the configuration file. The $releasever variable refers to the

current version of Fedora Core running on your server and the $basearch variable maps to the base

architecture of your server which is determined automatically. Here is an example of the use of thesevariables.

[repository-name]name=Fedora Core $releasever - $basearch - Basebaseurl=http://url.com/fedora/core/$releasever/$basearch/os/

Note: It is probably best to select yum update sites that use HTTP instead of FTP. There are a number

of reasons for this. FTP firewall rules are more difficult to implement than HTTP, outbound HTTP

access to the Internet is often already allowed in offices, and web servers are less likely to have

connection limits imposed on them, unlike FTP servers, which often have limits on the number of user

logins. Note: You can list multiple URLs in a baseurl statement like this and yum will try them all. If

you use multiple baseurl statements in each section then yum may act strangely, frequently only

selecting the last one in the list.

baseurl=url://server1/path/to/files/url://server2/path/to/files/url://server3/path/to/files/

Note: You can also place all your [repositoryid] sections in the yum.conf file. This was the
http://fedora.redhat.com/download/mirrors.htmlhttp://fedora.redhat.com/download/mirrors.htmlhttp://url.com/fedora/core/$releasever/$basearch/os/http://fedora.redhat.com/download/mirrors.htmlhttp://url.com/fedora/core/$releasever/$basearch/os/


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methodology used in some older versions of yum.

Note: The yum utility can be configured to match the downloaded RPMs against checksum files to help

protect against file corruption and malicious forgeries. This is set using the gpgcheck variable in the

.repo files. Checks are done when the value is set to 1, when set to 0, they are disabled. Here is an

example:

## File: example.repo#gpgcheck=1gpgkey=http://URL/example.key

Repositories will sometimes provide you with the URL for their checksum files and it is a good idea to

take advantage of them. This is a valuable feature.

How to Automate yum

Older versions of yum could be configured to run in the background as a daemon that was simple

named yum that used a unified yum.conf file for all its configuration data. Newer versions use the yum updatesd daemon instead. This uses the /etc/yum/yum updatesd.conf configuration file which governs

update frequency, the types of files to be downloaded and whether they should be automatically

installed using the yum command.

To get yum started, select the commands that match your OS version:

1. If using a newer version of Fedora / Redhat, make sure the yum updatesd package is installed.

[root@bigboy tmp]# yum y install yum-updatesd

2. Use the chkconfig command to get yum configured to start at boot:

[root@bigboy tmp]# chkconfig yum-updatesd on

[root@bigboy tmp]# chkconfig yum on

3. Use the service command to instruct the /etc/init.d yum script to start/stop yum after booting

[root@bigboy tmp]# service yum-updatesd start[root@bigboy tmp]# service yum-updatesd stop[root@bigboy tmp]# service yum start[root@bigboy tmp]# service yum stop

Note: Updating packages could cause programs written by you to stop functioning especially if theyrely on the older version's features or syntax. The yum daemon will do updates automatically; the yum

updatesd daemon won't do this unless the yum updatesd.conf file has been updated as shown here:

## File: /etc/yum/yum-updatesd.conf#

[main]do_update = yes
http://url/example.keyhttp://url/example.key


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Creating Your Own yum Server

An obvious advantage of using yum is that you can use it to update a yum server at your office with the

same directory structure of the mirror download sites on the Fedora Web site. The full set of steps to do

this is beyond the scope of this book, but there are some factors you should consider before doing this.

A small desktop PC with about five to six gigabytes of free disk space per distribution should be

sufficient to start with for a dedicated small business yum server. Large RPMs are about twenty fivemegabytes in size, and they are updated infrequently, so your network load should be minimal on

average with an update once or twice a week per server. In large server farms you may want to use a

more robust system that can handle many more clients, but before doing so, get trend data for its

network load to help your final decision. The configuration of the MRTG graphing tool is covered in

Chapter 22, " Monitoring Server Performance".

When established, you can then configure all your Fedora servers to use this local yum server for all

updates which will significantly reduce your Internet congestion and the associated bandwidth costs.

yum clients can access the yum server using either FTP or HTTP requests. If you need help in setting

these up, Chapter 15, "Linux FTP Server Setup", discusses Linux FTP servers and Chapter 20, "The

Apache Web Server", covers the Apache Web server for HTTP requests.

Note: When setting up an HTTP based yum server, you'll need to enable the viewing of directory

structures so that it will be easy for someone to use his or her Web browser to navigate down the

directories to double check the location of the yum files.

How to Automate yum

As of Fedora Core 6 the yum daemon has been named yum-updatesd, whereas in the past it wasjust called yum. To get yum started, select the commands that match your OS version:

1) Use the chkconfig command to get yum configured to start at boot:

[root@bigboy tmp]# chkconfig yum-updatesd on

[root@bigboy tmp]# chkconfig yum on

2) Use the service command to instruct the /etc/init.d yum script to start/stop yum after booting

[root@bigboy tmp]# service yum-updatesd start[root@bigboy tmp]# service yum-updatesd stop

[root@bigboy tmp]# service yum start[root@bigboy tmp]# service yum stop

Keeping Your System current with Yum

You can make the installed RPM packages on your system up to date with the latest patches using the

yum update command. When used without listing any packages afterwards, yum will attempt to update

them all. The yum update package name command updates only a particular RPM package.
http://www.linuxhomenetworking.com/wiki/index.php/Quick_HOWTO_:_Ch22_:_Monitoring_Server_Performancehttp://www.linuxhomenetworking.com/wiki/index.php/Quick_HOWTO_:_Ch15_:_Linux_FTP_Server_Setuphttp://www.linuxhomenetworking.com/wiki/index.php/Quick_HOWTO_:_Ch20_:_The_Apache_Web_Serverhttp://www.linuxhomenetworking.com/wiki/index.php/Quick_HOWTO_:_Ch20_:_The_Apache_Web_Serverhttp://www.linuxhomenetworking.com/wiki/index.php/Quick_HOWTO_:_Ch22_:_Monitoring_Server_Performancehttp://www.linuxhomenetworking.com/wiki/index.php/Quick_HOWTO_:_Ch15_:_Linux_FTP_Server_Setuphttp://www.linuxhomenetworking.com/wiki/index.php/Quick_HOWTO_:_Ch20_:_The_Apache_Web_Serverhttp://www.linuxhomenetworking.com/wiki/index.php/Quick_HOWTO_:_Ch20_:_The_Apache_Web_Server


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It is always advisable to use yum after installing Linux to make sure the latest versions of software are

installed for the sake of improved security and functionality. Here is an example of output of what to

expect with yum updating your system.

[root@bigboy tmp]# yum updateGathering header information file(s) from server(s)Server: Fedora Core 2 - i386 - BaseServer: Fedora Core 2 - i386 - Released UpdatesFinding updated packagesDownloading needed headersResolving dependenciesDependencies resolvedI will do the following:[install: kernel 2.4.22-1.2166.nptl.i686][update: samba-client 3.0.2-7.FC1.i386][update: binutils 2.14.90.0.6-4.i386].........Is this ok [y/N]: yGetting samba-client-3.0.2-7.FC1.i386.rpmsamba-client-3.0.2-7.FC1. 100% |=========================| 128 kB 05:01.........Running test transaction:Test transaction complete, Success!glibc-common 100 % done 1/127glibc 100 % done 2/127Stopping sshd:[ OK ]Starting sshd:[ OK ]bash 100 % done 3/127mozilla-nspr 100 % done 4/127sed 100 % done 5/127

...

...

...Completing update for pango - 65/127Completing update for samba-client - 66/127Completing update for binutils - 67/127.........Completing update for XFree86-font-utils - 127/127Kernel Updated/Installed, checking for bootloaderGrub found - making this kernel the defaultInstalled: kernel 2.4.22-1.2166.nptl.i686

Updated: pango 1.2.5-4.i386 samba-client 3.0.2-7.FC1.i386 binutils 2.14.90.0.6-4.i386 XFree86-Mesa-libGLU 4.3.0-55.i386 initscripts[root@bigboy tmp]#

Note: If you don't want to be prompted to install the files use the yum with the y switch.


17/28

Example of a yum Package Installation

Here is a sample installation of an individual package using yum. In this case the RPM installed is the

net snmp utils package:

[root@bigboy tmp]# yum -y install net-snmp-utils

Repository updates-released already added, not adding againRepository base already added, not adding againSetting up Install ProcessSetting up Repo: baserepomd.xml 100% |=========================| 1.1 kB 00:00Setting up Repo: updates-releasedrepomd.xml 100% |=========================| 951 B 00:00Reading repository metadata in from local filesbase : ############################################ 2622/2622primary.xml.gz 100% |=========================| 88 kB 00:00MD Read : ################################################## 229/229updates-re: ################################################## 229/229Resolving Dependencies

--> Populating transaction set with selected packages. Please wait.---> Package net-snmp-utils.i386 0:5.1.2-11 set to be installed--> Running transaction checkDependencies ResolvedTransaction Listing:Install: net-snmp-utils.i386 0:5.1.2-11

Downloading Packages:net-snmp-utils-5.1.2-11.i 100% |===================| 6.2 MB 00:48Running Transaction TestFinished Transaction TestTransaction Test SucceededRunning Transaction

Installing: net-snmp-utils 100 % done 1/1Installed: net-snmp-utils.i386 0:5.1.2-11Complete![root@bigboy tmp]#

Remember The Following Yum Facts

yum does its updates using TCP port 80 for http:// update URLs and uses passive FTP for ftp://

update URLs in /etc/yum.conf. This will have importance for your firewall rules.

More details on configuring yum can be obtained by running the man yum.conf command.

yum runs automatically each day. The cron file is located in /etc/cron.daily/.

Don't limit yourself to the default yum.conf URLs because they can become overloaded with

requests and make yum perform poorly.


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Installing Software From DEB FilesUnlike the Redhat, Fedora and Centos versions of Linux that use RPM packages, the Debian and

Ubuntu versions of Linux rely on packages in the DEB format. This section covers some of the most

important topics required for you to master their use.

How To Install DEBs Manually

There are generally two ways to install DEB files manually. The first method is by using a file

previously downloaded to your hard drive, and the other is to install the DEB from some sort of

removable media such as a CD ROM drive.

Using Downloaded Files

Download the DEBs (which usually have a file extension ending with .deb) into a temporary directory,

such as /tmp. The next step is to issue the dpkg install command to install the package. Here is an

example of a typical DEB installation command to install the ndiswrapper utilities package:

root@u-bigboy:~# dpkg --install ndiswrapper-utils_1.8-0ubuntu2_i386.debSelecting previously deselected package ndiswrapper-utils.(Reading database ... 70221 files and directories currently installed.)Unpacking ndiswrapper-utils (from ndiswrapper-utils_1.8-0ubuntu2_i386.deb) ...Setting up ndiswrapper-utils (1.8-0ubuntu2) ...root@u-bigboy:~#

Using CD ROMs

Installing DEB files from CDROM is similar to that with Fedora / Redhat. The difference is that theCDROM device name is /media/cdrom. The following procedure installs the ndiswrapper DEB that had

previously been copied to a disk.:

1. Insert the CD ROM, check the files in the /media/cdrom directory and then install the DEB.

root@u-bigboy:/tmp# mount /media/cdrom -o unhidemount: block device /dev/hdc is write-protected, mounting read-onlyroot@u-bigboy:/tmp# cd /media/cdromroot@u-bigboy:/media/cdrom# lsndiswrapper-utils_1.8-ubuntu2_i386.debroot@u-bigboy:/media/cdrom# dpkg --install ndiswrapper-utils_1.8-ubuntu2_i386.debSelecting previously deselected package ndiswrapper-utils.

(Reading database ... 70221 files and directories currently installed.)Unpacking ndiswrapper-utils (from ndiswrapper-utils_1.8-0ubuntu2_i386.deb) ...Setting up ndiswrapper-utils (1.8-0ubuntu2) ...root@u-bigboy:~#

2. When finished, eject the CD ROM

root@u-bigboy:/media/cdrom# cd /tmproot@u-bigboy:/tmp# umount /media/cdromroot@u-bigboy:/tmp# eject cdromroot@u-bigboy:/tmp#


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Note: Unlike the Fedora CD / DVD sets, Ubuntu Linux is distributed on a single CD / DVD. The

Ubuntu installation process downloads any additional packages it may need on demand from the

Internet. It is for this reason that you may find it easier to install Ubuntu software using the APT utility

which automatically download and install most of the packages you desire. The APT utility is covered

in a following section.

DEB Installation Errors

Sometimes the installation of DEB software doesn't go according to plan and you need to take

corrective actions. This section shows you how to recover from some of the most common errors you'll

encounter.

Failed Dependencies

As should be expected, packages often rely on the existence of other previously installed packages. This

will sometimes result in dpkg installations failing with dependency problems errors which really mean

that a prerequisite DEB needs to be installed. In the next example we're trying to install the mrtg contrib package, but it needs the mrtg package to be installed first beforehand.

root@u-bigboy:/tmp# dpkg --install mrtg-contrib_2.12.2-1_all.debSelecting previously deselected package mrtg-contrib.(Reading database ... 70759 files and directories currently installed.)Unpacking mrtg-contrib (from mrtg-contrib_2.12.2-1_all.deb) ...dpkg: dependency problems prevent configuration of mrtg-contrib:mrtg-contrib depends on mrtg (= 2.12.2-1); however:Package mrtg is not installed.

dpkg: error processing mrtg-contrib (--install):dependency problems - leaving unconfiguredErrors were encountered while processing:mrtg-contrib

root@u-bigboy:/tmp#

After installing the mrtg package, mrtg contrib was installed correctly. You can automatically install

prerequisite packages using the APT utility. This will be covered later in th echapter.

How to List Installed DEBs

The dpkg list command will list all the packages installed on your system

root@u-bigboy:~# dpkg --list

Desired=Unknown/Install/Remove/Purge/Hold| Status=Not/Installed/Config-files/Unpacked/Failed-config/Half-installed|/ Err?=(none)/Hold/Reinst-required/X=both-problems (Status,Err: uppercase=bad)||/ Name Version Description+++-===================-===================-================================ii ssh 4.1p1-7ubuntu4 Secure shell client and server.........root@u-bigboy:~#


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The output will be in six columns. The fourth column lists the name of the package, the fifth states the

package version, and the sixth and last provides a description.

The first three columns are each only a single character wide and provide very specific information

about the package as outlined in Table 6 3.

Table 6 3 Column Formatting for the dpkg command

Desired

State

(Col. 1)

Current

State

(Col. 2)

Error

State

(Col. 3)

Description

u Unknown: The package has never been installed

iInstalled: A privileged user has requested the installation of the

package

rRemove: A privileged user has requested the removal of the

package. Configuration files for the package most likely remain.

pPurge: A previously installed package has been removed.

Configuration files for the package have probably been removed.

hHold: A privileged user has requested that the package remain at

its current version with no automatic upgrades.

n Not Installed: The package is not installed

i Installed: The package is installed

cConfiguration Files Exist: Package was installed, but the

configuration files exist.

u Unpacked: Files have been unpacked, but not installed

f Failed: Configuration of the package has failed.

h Halt: The package installation failed to complete

h

Enforced Hold: Package upgrade is on hold because another

dependent package with a user defined hold requires this packageto remain not upgraded.

rReinstallation: The package is broken and requires a

reinstallation.

x The package is both broken and on enforced hold.

You can specify the desired package in which you are interested after the list option to get a listing


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specific to that package. Here we see a single listing for the openssh server package using this method.

root@u-bigboy:~# dpkg --list openssh-serverDesired=Unknown/Install/Remove/Purge/Hold| Status=Not/Installed/Config-files/Unpacked/Failed-config/Half-installed|/ Err?=(none)/Hold/Reinst-required/X=both-problems (Status,Err: uppercase=bad)||/ Name Version Description+++-===================-===================-

========================================ii openssh-server 4.2p1-7ubuntu3 Secure shell server, an rshdreplacementroot@u-bigboy:~#

You can also pipe the output of this command through the grep command if you are interested in only a

specific package. In this example we are looking for all packages containing the string dhcp in the

name.

root@u-bigboy:~# dpkg --list | grep dhcpii dhcp3-client 3.0.2-1ubuntu6 DHCP Clientii dhcp3-common 3.0.2-1ubuntu6 Common files - dhcp3* packagesroot@u-bigboy:~#

Listing Files Associated with DEBs

Sometimes you'll find yourself installing software that terminates with an error requesting the presence

of a particular file. In many cases the installation program doesn't state the DEB package in which the

file can be found. It is therefore important to be able to determine the origin of certain files, by listing

the contents for DEBs in which you suspect the files might reside.

Listing Files for Previously Installed DEBs

As stated previously, listing the files found in a package can be very useful. With dpkg, the listiles

option can provide this information easily. Here we list the files present in the openssh server package.

root@u-bigboy:~# dpkg --listfiles openssh-server........./var/run/sshd/usr/lib/sftp-server/usr/share/doc/openssh-serverroot@u-bigboy:~#

Listing Files in DEB Files

Download sites often have packages with different functions, but similar names. It is good to be able to

list the contents of a DEB package to verify you have the correct one. This can be done with the

contents option for dpkg as can be seen in this example.

root@u-bigboy:/tmp# dpkg --contents openssh-server_4.2p1-7ubuntu3_i386.deb.........


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-rw-r--r-- root/root 10444 2006-05-17 17:43:19 ./usr/share/man/man8/sshd.8.gz-rw-r--r-- root/root 1169 2006-05-17 17:43:19 ./usr/share/man/man8/sftp-server.8.gzdrwxr-xr-x root/root 0 2006-05-17 17:43:24 ./usr/share/doc/drwxr-xr-x root/root 0 2006-05-17 17:43:24 ./usr/share/doc/openssh-client/drwxr-xr-x root/root 0 2006-05-17 17:43:19 ./var/drwxr-xr-x root/root 0 2006-05-17 17:43:19 ./var/run/drwxr-xr-x root/root 0 2006-05-17 17:43:19 ./var/run/sshd/

...

...

...root@u-bigboy:/tmp#

Listing the DEB Package to Which a File Belongs

Searching for the ownership of a particular file is also simple when using the search option with dpkg.

In this example, we see that the /etc/syslog.conf file is a part of the sysklogd package.

root@u-bigboy:~# dpkg --search /etc/syslog.confsysklogd: /etc/syslog.confroot@u-bigboy:~#

Uninstalling DEBs

The dpkg remove command will erase an installed package as seen in this example.

root@u-bigboy:~# dpkg --remove ndiswrapper-utils(Reading database ... 70241 files and directories currently installed.)Removing ndiswrapper-utils ...

root@u-bigboy:~#

Which DEBs Will Start Up At Boot Time?

You can view and configure which DEBs will start at boot time is by using the update-rc.dcommand. A more detailed explanation will be provided in Chapter 7, "The Linux Boot Process".

Automatic DEB Updates with apt get

Like Fedora, Debian / Ubuntu Linux has its own package update application that will automaticallyretrieve packages from a network based repository. It is called the Advanced Package Tool (APT) and it

is the most commonly used command is apt get which we'll cover in more detail later

Configuring APT

APT uses the /etc/apt/sources.list file to instruct your server as to where to find the required packages

on your network. The default file locations in this file refer to a few trusted APT download websites on

the Internet.
http://www.linuxhomenetworking.com/wiki/index.php/Quick_HOWTO_:_Ch07_:_The_Linux_Boot_Processhttp://www.linuxhomenetworking.com/wiki/index.php/Quick_HOWTO_:_Ch07_:_The_Linux_Boot_Processhttp://www.linuxhomenetworking.com/wiki/index.php/Quick_HOWTO_:_Ch07_:_The_Linux_Boot_Process


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It is important to periodically resynchronize the APT package index files from the sources listed in

the /etc/apt/sources.list file. This updates your system with listings of the most current package

versions. This can be done with the apt get update command as seen here:

root@u-bigboy:/tmp# apt-get updateGet:1 http://security.ubuntu.com dapper-security Release.gpg [189B]Get:2 http://us.archive.ubuntu.com dapper Release.gpg [189B]Get:3 http://us.archive.ubuntu.com dapper-updates Release.gpg [189B].........Fetched 184kB in 2s (66.1kB/s)Reading package lists... Doneroot@u-bigboy:/tmp#

Note: If you install Ubuntu without Internet access, only a barebones set of packages will be installed

and the URL entries in the /etc/apt/sources.list file will be commented out, but the required packages

will be flagged for eventual installation in the dpkg database. When you get Internet access, uncomment

the URL entries and upgrade your installation with the apt get command which will update your system

with the full complement of required packages downloaded from the Web.You can also create an APT server on your own network if you don't want all your Debian / Ubuntu

servers to have Internet access. You'll have to update your sources.list file accordingly, but the full

configuration steps are beyond the scope of this book.

Keeping Your System current with APT

The apt get utility can be used to simultaneously upgrade all the packages on your system with the

upgrade option. When used without listing any packages afterwards, apt get will attempt to update them

all. The apt get upgrade package name command updates only a particular DEB package.

It is always advisable to use apt get after installing Linux to make sure the latest versions of softwareare installed for the sake of improved security and functionality. Here is an example of output of what to

expect; the y flag causes apt get to assume "yes" as the answer to all prompts and allows it to run non

interactively:

root@u-bigboy:/tmp# apt-get -y upgradeReading package lists... DoneBuilding dependency tree... DoneThe following packages have been kept back:linux-image-386

The following packages will be upgraded:capplets-data desktop-file-utils eog gdm gnome-about

...

...

...Setting up libgtk2.0-bin (2.8.18-0ubuntu1) ...Updating the IM modules list for GTK+-2.4.0...done.Updating the gdk-pixbuf loaders list for GTK+-2.4.0...done.

root@u-bigboy:/tmp#
http://security.ubuntu.com/http://us.archive.ubuntu.com/http://us.archive.ubuntu.com/http://security.ubuntu.com/http://us.archive.ubuntu.com/http://us.archive.ubuntu.com/


24/28

Example of an apt get Package Installation

Here is a sample installation of an individual package using yum. In this case the RPM installed is the

apache Web server package:

[root@ root@u-bigboy:/tmp# apt-get -y install apacheReading package lists... DoneBuilding dependency tree... DoneThe following extra packages will be installed:apache-common apache2-utils libapr0 libpcre3

Suggested packages:apache-doc apache-ssl apache-perl

The following NEW packages will be installed:apache apache-common apache2-utils libapr0 libpcre3

...

...

...Creating config file /etc/apache/httpd.conf with new version

Creating config file /etc/apache/srm.conf with new version

Creating config file /etc/apache/access.conf with new version

Creating config file /etc/apache/modules.conf with new version* Starting apache 1.3 web server......done.

root@u-bigboy:/tmp#

Remember The Following APT Facts

The APT utility's sources.list file primarily lists URLs using TCP port 80 (http://) for its updates

This will have importance for your firewall rules. More details on configuring yum can be obtained by running the man sources.list and the man

apt get commands.

Installing Software Using tar FilesAnother popular software installation file format is the tar file, which can frequently be obtained from

the Web sites of software developers, and online software libraries such as www.sourceforge.net.

The Linux tar command is used to archive files and typically have a .tar file extension in the file name.

These files are also frequently compressed in the gzip format, and when they do, their file extensionswill end with .tar.gz or .tgz. The commands to extract the data from either type are similar. When a tar

file is uncompressed, the command to extract the data is tar xvf filename.tar. When the archive is

compressed, the command to use is tar xzvf filename.tar.gz.

The tar file installation process usually requires you first to uncompress and extract the contents of the

archive in a local subdirectory, which frequently has the same name as the tar file. The subdirectory

will usually contain a file called README or INSTALL, which outlines all the customized steps to

install the software.


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Here are the initial steps to take to install tar based software:

1) Issue the tar command to extract the files.

[root@bigboy tmp]# tar -xvzf linux-software-1.3.1.tar.gzlinux-software-1.3.1/linux-software-1.3.1/plugins-scripts/...

......linux-software-1.3.1/linux-software-plugins.spec[root@bigboy tmp]#

This creates a subdirectory with the installation files inside.

[root@bigboy tmp]# lslinux-software-1.3.1 linux-software-1.3.1.tar.gz[root@bigboy tmp]#

2) Use the cd command to enter the subdirectory and follow the directions listed in the INSTALL and

README files:

[root@bigboy tmp]# cd linux-software-1.3.1[root@bigboy linux-software-1.3.1]# lsCOPYING install-sh missing pluginsdepcomp LEGAL mkinstalldirs plugins-scriptsFAQ lib linux-software.spec READMEHelper.pm Makefile.am linux-software.spec.in REQUIREMENTSINSTALL Makefile.in NEWS subst.in[root@bigboy linux-software-1.3.1]#

Software installation with tar files can be frustrating, frequently requiring the installation of other

supporting tar files, each with its own customized installation commands. RPMs, with the single

standardized command format, are usually easier to use and may be the better method to use for newerLinux users.

Installing Perl ModulesEven if you don't know how to program in Perl, you may find yourself having to install Perl modules to

get some of your software packages to work.

Modules can be installed manually by downloading the TAR files from www.cpan.org, the primary Perl

module site. The disadvantage is that this method doesn't automatically install any prerequisite modules

you may need. Another disadvantage, though small is that the perl module names usually have a double

colon (::) in their names, but the installation TAR file in which this module resides won't have thecolons in its name. For example version 1.74 of the Mail::Tools module has the file nameMailTools-1.74.tar.gz.

Modules can also be installed automatically using the perl command. We will cover both methods inthis section.


26/28

Manual Installation of Perl Modules

Most of the commonly used Perl modules can be downloaded from the CPAN website. The installation

steps are straightforward.

1. Browse the CPAN website, identify the module package you need and then download it using a

utility such as wget.

[root@bigboy tmp]# wget http://www.cpan.org/authors/id/M/MA/MARKOV/MailTools-1.74.tar.gz--15:07:36-- http://www.cpan.org/authors/id/M/MA/MARKOV/MailTools-1.74.tar.gz

=> `MailTools-1.74.tar.gz'Resolving www.cpan.org... 66.39.76.93Connecting to www.cpan.org|66.39.76.93|:80... connected.HTTP request sent, awaiting response... 200 OKLength: 47,783 (47K) [application/x-tar]

100%[===================================>] 47,783 100.88K/s

15:07:38 (100.51 KB/s) - `MailTools-1.74.tar.gz' saved [47783/47783]

[root@bigboy tmp]#

2. Extract the file from the package with the tar command.

[root@bigboy tmp]# tar -xzvf MailTools-1.74.tar.gzMailTools-1.74/MailTools-1.74/t/.........MailTools-1.74/ChangeLogMailTools-1.74/MANIFEST

[root@bigboy tmp]#

3. Enter the newly created directory with the same name as the TAR file, and install the module with

the following commands.

perl Makefile.PL

make

make test

[root@bigboy tmp]# cd MailTools-1.74[root@bigboy MailTools-1.74]# perl Makefile.PLChecking for Net::SMTP...okChecking for Net::Domain...ok

Checking for IO::Handle...okChecking if your kit is complete...Looks goodWriting Makefile for Mail[root@bigboy MailTools-1.74]# makecp Mail/Cap.pm blib/lib/Mail/Cap.pmcp Mail/Mailer/rfc822.pm blib/lib/Mail/Mailer/rfc822.pm.........
http://www.cpan.org/authors/id/M/MA/MARKOV/MailTools-1.74.tar.gzhttp://www.cpan.org/authors/id/M/MA/MARKOV/MailTools-1.74.tar.gzhttp://www.cpan.org/authors/id/M/MA/MARKOV/MailTools-1.74.tar.gzhttp://www.cpan.org/authors/id/M/MA/MARKOV/MailTools-1.74.tar.gzhttp://www.cpan.org/authors/id/M/MA/MARKOV/MailTools-1.74.tar.gzhttp://www.cpan.org/authors/id/M/MA/MARKOV/MailTools-1.74.tar.gz


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Manifying blib/man3/Mail::Util.3pmManifying blib/man3/Mail::Address.3pm[root@bigboy MailTools-1.74]# make testPERL_DL_NONLAZY=1 /usr/bin/perl "-MExtUtils::Command::MM" "-e" "test_harness(0,'blib/lib', 'blib/arch')" t/*.tt/extract.....ok......

...All tests successful.Files=7, Tests=95, 2 wallclock secs ( 1.28 cusr + 0.29 csys = 1.57 CPU)[root@bigboy MailTools-1.74]#

Your Perl module installation should now be complete.

Note: The output of the perl Makefile.PL command will tell you whether there are any other required

modules. You can either install them all manually, running the risk of having to install more

prerequisite modules for these prerequisite modules, or you can use automated updates which will be

covered next.

Automatic Installation of Perl Modules

Modules can be installed automatically using the perl utility but you must first install the prerequisitencftp and perl-CPAN package to download the packages from CPAN.

[root@bigboy tmp]# yum -y install ncftp perl-CPAN

After the package installed you can use the following perl command to enter the CPAN utility.

perl -MCPAN -e shell

The first time it is run, Perl will prompt you for a number of configuration options. In most cases the

defaults will be sufficient. After the initial setup is complete you will have a cpan> command prompt

cpan>

Installation of modules can then be done with the install command followed by the name of the module.

In this example we install the Mail::Audit module using the CPAN utility.

[root@bigboy tmp]# perl -MCPAN -e shellTerminal does not support AddHistory.

cpan shell -- CPAN exploration and modules installation (v1.7602)

ReadLine support available (try 'install Bundle::CPAN')

cpan> install Mail::AuditCPAN: Storable loaded okLWP not availableCPAN: Net::FTP loaded okFetching with Net::FTP: ftp://archive.progeny.com/CPAN/authors/01mailrc.txt.gz......
ftp://archive.progeny.com/CPAN/authors/01mailrc.txt.gzftp://archive.progeny.com/CPAN/authors/01mailrc.txt.gz


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...Installing /usr/share/man/man3/Mail::Audit::MAPS.3pmAppending installation info to /usr/lib/perl5/5.8.8/i386-linux-thread-multi/perllocal.pod/usr/bin/make install -- OK

cpan> exitTerminal does not support GetHistory.

Lockfile removed.[root@bigboy tmp]#

The exit command allows you to return to the Linux command prompt and your Perl module should be

fully installed.

Updating Your Perl Modules

Upgrading or updating your modules to the latest version can also be done using the perl command line

utility like this.

[root@bigboy tmp]# perl -MCPAN -we 'CPAN::Shell->install(CPAN::Shell->r)'

This is a simple process, but make sure you have internet connectivity first.

ConclusionThis is just the beginning. If the software you install is intended to make your Linux machine

permanently run an application such as a Web server, mail server, or any other type of server you have

to know how to get the software activated when the system reboots. This is covered in Chapter 7, "The

Linux Boot Process". Subsequent chapters cover the use, configuration, testing, and troubleshooting of

many of the most popular Linux server applications used today.
http://www.linuxhomenetworking.com/wiki/index.php/Quick_HOWTO_:_Ch07_:_The_Linux_Boot_Processhttp://www.linuxhomenetworking.com/wiki/index.php/Quick_HOWTO_:_Ch07_:_The_Linux_Boot_Processhttp://www.linuxhomenetworking.com/wiki/index.php/Quick_HOWTO_:_Ch07_:_The_Linux_Boot_Processhttp://www.linuxhomenetworking.com/wiki/index.php/Quick_HOWTO_:_Ch07_:_The_Linux_Boot_Process

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