CentOS/RHEL: Configuring and working with the YUM utility

Yum is a utility for working with RPM packages for CentOS and RedHat OS. 

All settings are carried out in the configuration file:

vim /etc/yum.conf

By default, there are the following settings:

[main]
gpgcheck=1
installonly_limit=3
clean_requirements_on_remove=True
best=True

gpgcheck - yum will authenticate packets;
installonly_limit - maximum number of versions that can be installed for a specific package;
clean_requirements_on_remove - when deleting a package, delete and all its dependencies;
best - when updating, always try to install the latest version of the package.

To configure yum to work through a proxy, add the following parameters:

proxy=http://proxyhost:8080
proxy_username=proxyname
proxy_password=proxypass
proxy_auth_method=basic

where proxy - proxy server address and port;
proxy_username - username for authentication;
proxy_password - user password;
proxy_auth_method - authentication method ("any" by default).

Basic operations with yum:

"yum list" - display all installed packages and available in repositories packages;
"yum list installed" - display all installed packages only;
"yum list available" - display available in repositories packages only;
"yum check-update" - checking for updates for packages;
"yum update package_name" - updating the version of the specified package;
"yum update" - updating all installed packages;
"yum install package_name" - installation of the specified package;
"yum remove package_name" - delete specified package.