如果不理解該命令，可以先去了解：yum 倉庫管理 yum-config-manager

在使用該命令的時候碰到以下問題：

[root@iZbp115r5t4hzamv0snvm1Z cim]# yum-config-manager --add-repo https://download.opensuse.org/repositories/home:/Alexander_Pozdnyakov/CentOS_7/
-bash: yum-config-manager: command not found

這是因為系統默認沒有安裝這個命令，這個命令在 yum-utils 包里，安裝該包即可。

# yum -y install yum-utils # 執行此命令即可

操作流程如下：

[root@iZbp115r5t4hzamv0snvm1Z cim]# yum -y install yum-utils
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
 * webtatic: us-east.repo.webtatic.com
Resolving Dependencies
--> Running transaction check
---> Package yum-utils.noarch 0:1.1.31-54.el7_8 will be installed
--> Processing Dependency: python-kitchen for package: yum-utils-1.1.31-54.el7_8.noarch
--> Processing Dependency: libxml2-python for package: yum-utils-1.1.31-54.el7_8.noarch
--> Running transaction check
---> Package libxml2-python.x86_64 0:2.9.1-6.el7.5 will be installed
---> Package python-kitchen.noarch 0:1.1.1-5.el7 will be installed
--> Processing Dependency: python-chardet for package: python-kitchen-1.1.1-5.el7.noarch
--> Running transaction check
---> Package python-chardet.noarch 0:2.2.1-3.el7 will be installed
--> Finished Dependency Resolution

Dependencies Resolved

=================================================================================================
 Package                   Arch              Version                       Repository       Size
=================================================================================================
Installing:
 yum-utils                 noarch            1.1.31-54.el7_8               base            122 k
Installing for dependencies:
 libxml2-python            x86_64            2.9.1-6.el7.5                 base            247 k
 python-chardet            noarch            2.2.1-3.el7                   base            227 k
 python-kitchen            noarch            1.1.1-5.el7                   base            267 k

Transaction Summary
=================================================================================================
Install  1 Package (+3 Dependent packages)

Total download size: 863 k
Installed size: 4.3 M
Downloading packages:
(1/4): python-chardet-2.2.1-3.el7.noarch.rpm                              | 227 kB  00:00:00
(2/4): libxml2-python-2.9.1-6.el7.5.x86_64.rpm                            | 247 kB  00:00:00
(3/4): yum-utils-1.1.31-54.el7_8.noarch.rpm                               | 122 kB  00:00:00
(4/4): python-kitchen-1.1.1-5.el7.noarch.rpm                              | 267 kB  00:00:00
-------------------------------------------------------------------------------------------------
Total                                                            4.6 MB/s | 863 kB  00:00:00
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
  Installing : python-chardet-2.2.1-3.el7.noarch                                             1/4
  Installing : python-kitchen-1.1.1-5.el7.noarch                                             2/4
  Installing : libxml2-python-2.9.1-6.el7.5.x86_64                                           3/4
  Installing : yum-utils-1.1.31-54.el7_8.noarch                                              4/4
  Verifying  : libxml2-python-2.9.1-6.el7.5.x86_64                                           1/4
  Verifying  : python-kitchen-1.1.1-5.el7.noarch                                             2/4
  Verifying  : yum-utils-1.1.31-54.el7_8.noarch                                              3/4
  Verifying  : python-chardet-2.2.1-3.el7.noarch                                             4/4

Installed:
  yum-utils.noarch 0:1.1.31-54.el7_8

Dependency Installed:
  libxml2-python.x86_64 0:2.9.1-6.el7.5            python-chardet.noarch 0:2.2.1-3.el7
  python-kitchen.noarch 0:1.1.1-5.el7

Complete!