centos 7安装 yum

[root@ecs-88500735 ~]# cat /etc/redhat-release
CentOS Linux release 7.9.2009 (Core)
[root@ecs-88500735 ~]# uname -i
x86_64
[root@ecs-88500735 ~]# 

https://mirrors.163.com/centos/7.9.2009/os/x86_64/Packages/

[root@ecs-88500735 ~]# mkdir mirrors.163.com_centos_7.9.2009_os_x86_64_Packages
[root@ecs-88500735 ~]# cd mirro*
[root@ecs-88500735 mirrors.163.com_centos_7.9.2009_os_x86_64_Packages]# wget https://mirrors.163.com/centos/7.9.2009/os/x86_64/Packages/yum-metadata-parser-1.1.4-10.el7.x86_64.rpm
--2022-05-18 12:41:05--  https://mirrors.163.com/centos/7.9.2009/os/x86_64/Packages/yum-metadata-parser-1.1.4-10.el7.x86_64.rpm
正在解析主机 mirrors.163.com (mirrors.163.com)... 117.147.202.12
正在连接 mirrors.163.com (mirrors.163.com)|117.147.202.12|:443... 已连接。
已发出 HTTP 请求，正在等待回应... 200 OK
长度：28348 (28K) [application/x-redhat-package-manager]
正在保存至: “yum-metadata-parser-1.1.4-10.el7.x86_64.rpm”

100%[======================================>] 28,348      --.-K/s 用时 0.01s   

2022-05-18 12:41:05 (1.90 MB/s) - 已保存 “yum-metadata-parser-1.1.4-10.el7.x86_64.rpm” [28348/28348])

[root@ecs-88500735 mirrors.163.com_centos_7.9.2009_os_x86_64_Packages]# wget https://mirrors.163.com/centos/7.9.2009/os/x86_64/Packages/yum-plugin-fastestmirror-1.1.31-54.el7_8.noarch.rpm
--2022-05-18 12:41:20--  https://mirrors.163.com/centos/7.9.2009/os/x86_64/Packages/yum-plugin-fastestmirror-1.1.31-54.el7_8.noarch.rpm
正在解析主机 mirrors.163.com (mirrors.163.com)... 117.147.202.12
正在连接 mirrors.163.com (mirrors.163.com)|117.147.202.12|:443... 已连接。
已发出 HTTP 请求，正在等待回应... 200 OK
长度：35216 (34K) [application/x-redhat-package-manager]
正在保存至: “yum-plugin-fastestmirror-1.1.31-54.el7_8.noarch.rpm”

100%[======================================>] 35,216       173KB/s 用时 0.2s   

2022-05-18 12:41:21 (173 KB/s) - 已保存 “yum-plugin-fastestmirror-1.1.31-54.el7_8.noarch.rpm” [35216/35216])
[root@ecs-88500735 mirrors.163.com_centos_7.9.2009_os_x86_64_Packages]# wget https://mirrors.163.com/centos/7.9.2009/os/x86_64/Packages/yum-3.4.3-168.el7.centos.noarch.rpm
--2022-05-18 12:43:12--  https://mirrors.163.com/centos/7.9.2009/os/x86_64/Packages/yum-3.4.3-168.el7.centos.noarch.rpm
正在解析主机 mirrors.163.com (mirrors.163.com)... 117.147.202.12
正在连接 mirrors.163.com (mirrors.163.com)|117.147.202.12|:443... 已连接。
已发出 HTTP 请求，正在等待回应... 200 OK
长度：1298856 (1.2M) [application/x-redhat-package-manager]
正在保存至: “yum-3.4.3-168.el7.centos.noarch.rpm”

100%[======================================>] 1,298,856    832KB/s 用时 1.5s   

2022-05-18 12:43:14 (832 KB/s) - 已保存 “yum-3.4.3-168.el7.centos.noarch.rpm” [1298856/1298856])

[root@ecs-88500735 mirrors.163.com_centos_7.9.2009_os_x86_64_Packages]# ls
yum-3.4.3-168.el7.centos.noarch.rpm
yum-metadata-parser-1.1.4-10.el7.x86_64.rpm
yum-plugin-fastestmirror-1.1.31-54.el7_8.noarch.rpm
[root@ecs-88500735 mirrors.163.com_centos_7.9.2009_os_x86_64_Packages]# rpm -ivh *rpm
准备中...                          ################################# [100%]
正在升级/安装...
   1:yum-metadata-parser-1.1.4-10.el7 ################################# [ 33%]
   2:yum-plugin-fastestmirror-1.1.31-5################################# [ 67%]
   3:yum-3.4.3-168.el7.centos         ################################# [100%]
[root@ecs-88500735 mirrors.163.com_centos_7.9.2009_os_x86_64_Packages]# ls
yum-3.4.3-168.el7.centos.noarch.rpm
yum-metadata-parser-1.1.4-10.el7.x86_64.rpm
yum-plugin-fastestmirror-1.1.31-54.el7_8.noarch.rpm
[root@ecs-88500735 mirrors.163.com_centos_7.9.2009_os_x86_64_Packages]# yum --version
3.4.3
  已安装： rpm-4.11.3-48.el7_9.x86_64 在 2022-05-16 04:31
  构建    ：CentOS BuildSystem  在 2021-11-24 16:33
  已提交：Michal Domonkos  ，共 2021-11-01 

  已安装： yum-3.4.3-168.el7.centos.noarch 在 2022-05-18 04:44
  构建    ：CentOS BuildSystem  在 2020-10-01 17:03
  已提交：CentOS Sources  ，共 2020-09-29 

  已安装： yum-plugin-fastestmirror-1.1.31-54.el7_8.noarch 在 2022-05-18 04:44
  构建    ：CentOS BuildSystem  在 2020-05-12 16:27
  已提交：Michal Domonkos  ，共 2020-03-12