Configuration and use of Yum source


Yum (full name: yellow dog updater, modified) is based on RPM package management. It can automatically download and install RPM packages from the specified server. It can automatically handle dependencies, and install all dependent packages at one time without tedious downloading and installation.

Local Yum warehouse: the server provides services for the local machine

Components of Yum warehouse

1. data: including all software package files

2. metadata: refers to data files, including package name, version information, file list contained in each package, dependencies between packages, and package grouping information

Server: owns all contents of the CD
Client: specify the local computer and as the server, and write a configuration file
Note: the wrong configuration file will affect the correct file

Experiment: configure local Yum source; Operating system: CentOS 7
Mount the CD (mount the CD file /dev/cdrom to the mount point /mnt)

Create directory /repo/cos7dvd

Copy the attached CD file to the directory /repo/cos7dvd

Clean up old configurations, unavailable configurations, and configurations created by others to prevent interference

[[email protected] ~]# mv /etc/yum.repos.d/*.repo /etc/yum.repos.d/oldrepo/

Quickly add new software sources

[[email protected] ~]# vim /etc/yum.conf

Clean up Yum cache data

To improve the retrieval speed, yum caches data locally. When the address of the software park changes or the warehouse needs to be checked, it is recommended to clean up all caches first

 Use of the yum command

Yum query function

    yum [options] [command] [package …]

-y: By default, yum needs to be in interactive mode, -y means to automatically provide a yes response

Search: search for a software name or keyword

List: lists all packages and names managed by yum

Info: same as above, also similar to rpm -qai

Provides: find that the command is generated by software installation, similar to rpm -df

Repolist: lists all available repos

Yum install, upgrade, demote, uninstall features

Install: followed by the software to be installed

Reinstall: followed by the software to be reinstalled

Update: followed by the software to be upgraded

Check update: check the available upgrade packages

Downgrade: followed by the version to which you want to downgrade

Remove: uninstall the software


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