Red Hat Package Management

 

Red Hat Subscription Management:

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1. Red Hat Subscription provides tool that can be used to entitle machine to product subscription.
2. Subscription allowing administrators to get updates to software packages and track information about the support contract and subscription used by the system.
3. Standard tools such as Package Kit and yum can be obtain software packages and updates through a content distribution network    provided by Red Hat. 

Register:- This allow subscription manager to uniquely inventory the system.

Subscribe:- Subscription have specific levels of support, expiration dates and defaults repositories.

Enable Repositories:- Enable multiple repositories by default with each subscription.

Review and Track:- Subscription information can be viewed locally on a specific system or for an account, in either Red Hat Customer Portal Subscription page or Subscription Asset Manager (SAM)

System Registration:

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1. There are a number of different ways to register a system with Red Hat Customer Portal.
2. There is a graphical interface that you can access with GNOME application or through the web console service and also there is command line.
3. Once Registration successfully done, your system is ready to take the updates or install new software from Red Hat.

Note: "GNU Network Object Environment Model is a free & open source desktop environment for Linux & other Unix operating system. It's started from 15 August 1997."

Graphical Mode

1. Activities Show All Redhat Subscription Manger
2. Activities Type in Search Subscription

Terminal Mode

1) Register a system to Red Hat Account

#subscription-manager register -username=name -password=password

2) View Available Subscription

#subscription-manager list -available | less

3) Auto Attached a Subscription

#subscription-manager attached -auto

4) Alternatively Attached a Subscription From Specific Pool

#subscription-manager attached -pool=poolId

5) View Consumed Subscriptions

#subscription-manager list -consumed

6) Unregister a System

#subscription-manager unregister

Entitlement Certificates:

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An entitlement is a subscription that has been attached to a system. Digital certificates are used to store current information about entitlements on the local system.

Note: "Once registerd, entitlement certificates are stored in /etc/pki and its subdirectories."

1. /etc/pki/product: Contains certificate indicating which Red Hat products are installed on the System.
2. /etc/pki/consumer: Contain certificate identifying the Red Hat account to which the system is registerd.
3. /etc/pki/entitlement: Contain certificate indicating which subscription are attached to the system.

Red Hat Package Manager:

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1. RPM (Red Hat Package Manager) is originally developed by Red Hat and most popular package management utility in Linux Platform.
2. RPM is distributed under the terms of the GPL (General Public License).
3. RPM provides a standard way to package software for distribution
4. It allows administrator to track where files installed by the software package and which one need to be removed.
5. Package management system take all the various files containing programs and data, documentation and configuration information and place them in one specially formatted file a package file with an extension of ".rpm".
6. RPM maintains a database of installed packages, which enables powerful and fast queries. The RPM database is inside /var/lib, and the file is named __db*.

Package Identification:

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vsftpd-3.0.3-28.el8.x86_64.rpm

vsftpd     Name

-3.0.3     Version

-28.el8    Release

.x86_64    Architecture

.rpm       Extension

RPM Package made up of three component:

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A) The file installed by the package

B) Information about package (metadata)

1. Name
2. Version
3. Release
4. Arch

C) Scripts that may run when package is

1. Installed
2. Updated
3. Removed

RPM(Redhat Package Manager) Mode:

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1. Install: It is used for install any rpm package
2. Upgrade: It is used to update any existing rpm packages
3. Remove:  To uninstall any installed rpm package from system
4. Verify:  Verify the rpm packages
5. Query:   It is used to find rpm package is installed or not

Note:- "A repository (or repo) is a type of centrally located storage where you can keep all your project's files and resources".

Updates and Patches:

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1. When the upstream source code for a software package is patched by Red Hat, a complete RPM package is generated.
2. If a package is newly added to a system only the latest version of that package is needed, not every version of the package since the first release.
3. When you update the old version of the package is removed and the new version is installed.

#rpm [option] package_name

-qa	List all installed packages
-ql	Display information about a package
-qi	List all files included in a package
-qc	List configuration files included in a package
-qd	List documentation files included in a package
-q --changelog	Show a short summary of the reason for a new package release
-q --script	Display the shell scripts included in a package
-i	Installing a rpm package
-v	Verbose
-h or -- percent	Display progression bar in hash or percentage
-U	For upgrading the existing installed package
-e	To remove or erase any installed package

YUM Package Manager:

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1. YUM(Yellow dog Updater Modified) is created by Terra Soft, ported to many Linux distributions.
2. YUM is used to managed packages like installing,updating,removing and querying.
3. The YUM command searches packages and their dependencies so they may be installed together and resolve dependency issues.
4. The main configuration file for yum is /etc/yum.conf with additional repository configuration files located in the /etc/yum.repos.d directory.

How we can configure YUM server in RHEL 8

YUM COMMAND CHEAT SHEET

Install,Uninstall & Upgrade Packages
Command	Example	Functionality
install	yum install httpd	Install a package from yum repository
remove	yum remove httpd	remove install package and its dependecies from system
erase	yum erase httpd	Similar to remove command
update	yum update or yum update httpd	Update one or more package on the system
update-to	yum update-to httpd-2.7-1.1	Update one or more package to a specific version
upgrade	yum upgrade	Update all package to the latest version
reinstall	yum reinstall httpd	Reinstall the current version of a specific package
autoremove	yum autoremove httpd	Remove a package and all other unnecessary packages
downgrade	yum downgrade httpd	Downgrade a specific package to an earlier version
swap	yum swap httpd ntfs-3g	Remove package and install another
localinstall	yum localinstall http://127.0.0.1/baseos/httpd-1.b.c.rpm	Install a package from local repository
groupinstall	yum groupinstall "group name"	Install package from a specific group

Base Package Commands
Command	Example	Functionality
list	yum list all	List package names from repositories
info	yum info httpd	Show information about a specific package
search	yum search apache	Search for a package name and description
updateinfo	yum updateinfo baseos	Show information about available package updates
check-update	yum check-update	Show available package from enabled repositories
grouplist	yum grouplist	Show names and available package groups
deplist	yum deplist vsftpd	Show dependencies for a specific package
provides	yum provides "*/bin/zsh"	Locate the package that provided a specific file
groupinfo	yum groupinfo "group name"	Show description and contents of a package group
help	yum help or yum help list	Display yum help information or help on sub command

Manging YUM Repos
Command	Example	Functionality
repolist	yum repolist	List the available software repositories
repo-pkgs	yum repo-pkgs baseos list	Use packages in a specific repository
repoinfo	yum repoinfo baseos	Show information about enabled repositories
makecache	yum makecache	Download repository data to cache

Troubleshooting YUM
Command	Example	Functionality
clean	yum clean packages or yum clean all	Clean out all cached package data and metadata
check	yum check	Check local RPM db for problems
history	yum history list or yum history undo or yum history redo	View and use yum transactions
fssnapshot	yum fs filters	Show LVM snapshots

Group installing and Removing:

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Yum also has a concept of groups, which are collection of related software together for a particular purpose.

In RHEL 8 have two types of group

1. Regular Group: This group are collection of packages
2. Environment Group: This group are collection of regular groups

YUM Group Command
Command	Example	Functionality
group list	yum group list or yum grouplist	Command will show the names of installed and available groups.
group list hidden	yum group list hidden	Command will show you hidden groups
groupinfo	yum group info or yum groupinfo	Command will show information about a group
group install group_name	yum group install "Group Name"	Command will install Group
group summary	yum group summary	To view number of installed groups,available group

Thanks & Regards

Abhishek Pathak

+91-9621134014

abhishek9621134014@outlook.com