- Software is the basic o any operating system, allowing you install and use different utilities.
- In Linux, software is distributed through the use of packages, which contain the actual software files.
- Each distribution of Linux has its own package manage system.
- For RedHat, there are two package management systems :RPM &YUM.
Working with RPM:
- RPM stands for RedHat Package Manger).
- RPM is default package installation tool in Linux operating system.
- By using RPM we can install, upgrade, query, verify and remove the packages.
- Before diving into package management. Lets look at the naming convention used by the system to describe packages
Package Parameters:
postfix -2.6.6-2.e16.x86_64.rpm
Parameters Description:
postfix – package name
-2.6.6-2.e16 – version name
x86_64 – Architecture number
rpm – Extension of package
Method of Installation:
There are two ways of installations. They are
- Standalone
- Network
Standalone:
In this type, we can install the packages through any removable media or through dump.
Installing and Removing packages:
Syntax:
#rpm <options> <pkg-name> --force --aid
Parameters description:
Option:
i -> installs a given package
v -> verbose output
h -> shows hash progress when
u -> Upgrades a given package
e ->Removes a given package
–force -> Install the package with forcefully
–aid -> Install the package along with Dependencies
–nodeps -> To erase an package without dependencies
Quary Options (with -q):
Syntax:
#rmp <options> <pkg-name>
Options
c -> List all config files
d -> Lists all documentation files.
i -> Displays information about the package.
l -> Lists the file in a package.
s -> Status of the package.
Verify options (with -v):
-a -> Queries all packages
f -> Displays information about the specified file.
For installing an application.
#rpm -ivh nano-2.2.6-1.x86_64.rpm
For installing an application with forcefully.
#rpm -ivh nano-2.2.6-1.x86_64.rpm --force
If you want to upgrade this package (because you know that it is already installed), you substitute the -i option for -U
#rpm -Uvh nano-2.2.6-1.x86_64.rpm
For uninstalling a package
#rpm -e nano
You can always reinstall the package at a later date if you keep the .rpm file on your system.
#rpm -ivh -replacepkgs nano-2.2.6-1.x86_64 .rpm
Tip:
A common situation to run into the job is having to install a package that is already installed. You don’t have to go through the trouble of uninstalling the package first only to reinstall it. You can use the -replacepkg option alongside the regular install option to over ride an existing installation.
Query the installed system package for nano:
#rpm -qa|grep nano
Query the information from the nano package:
#rpm -qi nano
Suppose you are looking around on your new RedHat installation and a file but aren’t sure what it does.You can use the -f option to query the package that the file might belongs to, possibly giving you a better idea of what that file might be used for.
Find out where the /etc/syslog.conf file came from by doing the following.
#rmp -qf /etc/syslog .conf
Use the -c option to find all config files.
#rmp -qc rsyslog
To find the documentation files for a given package.
#rpm -qd rsyslog
To listing of all files that come with the package.
#rpm -ql rsyslog
To find out whether a package has any dependencies:
#rpm -qR rsyslog
YUM
- yum stands for yellowdog update modifier
- In this section, we look at the exact same tasks, except this time. We use the more flexible yum utility.
- The yum command has access to repositories where tons of packages are kept and can install, upgrade or remove them for you automatically.
- yum also takes care of resolving and installing any dependencies for you, which the rpm command can’t do.
- yum is an interactive tool which waits for the confirmation of a user.
- yum is a default package management tool tool in RedHat O/S.
- Using this tool we can install the required packages with dependencies.
Syantax:
yum <options> <command> <packagename>
Option:
c -> Specifies the location of the config file.
q -> Specifies quit, no output.
y -> /to always answer yes to prompts.
v -> Provides verbose output
Commands:
yum clean | Removes cached data |
yum erase | Removes a package from the system |
yum list | Display available packages |
yum install | Install a package on the system |
yum search | Enables you to search for a package |
yum update | Updates a package |
yum grouplist | Display available package groups |
yum groupinstall | Install a package with in a group |
yum groupremove | Removes a packages with in a group |