What is Yum ?
YUM Stands for Yellowdog Updater Modified. YUM is an interactive, rpm based package manager. Yum is available in different Linux OS Like Redhat , Centos , Fedora etc. It can also perform installation of new packages, removal of old packages and perform queries on the installed and/or available packages among many other commands/services.
Yum Solves the Package dependencies problems which is generally found in RPM Command .
Syntax : yum [options] [command] [package …]
Example :1 Install a Package (e.g Thunderbird)
In above command, to install Thunderbird we have press Y for confirmation, so to avoid this we can pass 'y' option in yum command so that it automatically confirm and install the package.
[root@master ~]# yum -y install thunderbird
Example:2 Remove a Package (e.g thunderbird)
Example:3 Check whether any updates are available for your system or not .
Below Command will list no of the packages to be updated
[root@master ~]# yum check-update
To update a particular package to a specific version , use 'update-to' option in yum command.
Example:4 To display information about a specific package(e.g httpd) use below command
To List the information about available packages , example
Example:5 Search packages when we know something about the package but aren’t sure of it’s name
Example:6 To find out which package provides a specific file like '/etc/inittab'
Example:7 To Install all the packages of specific Group, use 'groupinstall' option.
To install all packages of 'Development tools' :
[root@master ~]# yum groupinstall 'Development tools'
To list all the available groups from all yum repos.
[root@master ~]# yum grouplist
Example:8 To view history of a package what had happened in past transactions like when it was installed , upgraded and removed.
Syntax : # yum history <info/list/packages-list/packages-info/summary> package-Name
Example:9 View and install security updates on your system. First Install the security plugin using below yum command
[root@master ~]# yum install yum-security
To list all Available Security Updates
[root@master ~]# yum list-security