CentOS7 重装yum

1. 卸载 yum

rpm -aq|grep yum|xargs rpm -e --nodeps

2. 下载rpm包

包仓库 :http://mirrors.163.com/centos/7/os/x86_64/Packages/

可以使用wget 方式下载,如下:

wget http://mirrors.163.com/centos/7/os/x86_64/Packages/yum-3.4.3-163.el7.centos.noarch.rpm 

也可以直接在仓库搜索点击下载,如下 :

下载如下包:

python-2.7.5-88.el7.x86_64.rpm
python-iniparse-0.4-9.el7.noarch.rpm
python-libs-2.7.5-88.el7.x86_64.rpm
python-pycurl-7.19.0-19.el7.x86_64.rpm
python-urlgrabber-3.10-10.el7.noarch.rpm
yum-3.4.3-167.el7.centos.noarch.rpm
yum-metadata-parser-1.1.4-10.el7.x86_64.rpm
yum-plugin-fastestmirror-1.1.31-53.el7.noarch.rpm

(如果没有，可以调整小版本号即可）

[root@pys ff]# ll
总用量 7452
-rw-r--r-- 1 root root   97976 9月  24 00:01 python-2.7.5-88.el7.x86_64.rpm
-rw-r--r-- 1 root root   39800 7月   4 2014 python-iniparse-0.4-9.el7.noarch.rpm
-rw-r--r-- 1 root root 5918924 9月  24 00:03 python-libs-2.7.5-88.el7.x86_64.rpm
-rw-r--r-- 1 root root   82396 11月 21 2016 python-pycurl-7.19.0-19.el7.x86_64.rpm
-rw-r--r-- 1 root root  111048 9月  23 22:20 python-urlgrabber-3.10-10.el7.noarch.rpm
-rw-r--r-- 1 root root 1298672 9月  23 21:53 yum-3.4.3-167.el7.centos.noarch.rpm
-rw-r--r-- 1 root root   28348 9月  23 21:53 yum-metadata-parser-1.1.4-10.el7.x86_64.rpm
-rw-r--r-- 1 root root   35004 9月  23 21:54 yum-plugin-fastestmirror-1.1.31-53.el7.noarch.rpm

执行

rpm -ivh python-* 

安装python*包 ;

执行

rpm -ivh yum-metadata-parser-1.1.4-10.el7.x86_64.rpm

安装yum-metadata-parser-1.1.4-10.el7.x86_64.rpm包 ;

yum-plugin-fastestmirror-1.1.31-52.el7.noarch.rpm 与yum-3.4.3-163.el7.centos.noarch.rpm 相互依赖 ;

所以执行

rpm -ivh yum-plugin-fastestmirror-1.1.31-52.el7.noarch.rpm yum-3.4.3-163.el7.centos.noarch.rpm 

两个包同时安装 ;

输入 yum -v 测试yum 安装;

4. 修改yum源

cd /etc/yum.repos.d 进入 yum源目录 ;

从http://mirrors.163.com/.help/CentOS7-Base-163.repo 下载yum源,上传至 /etc/yum.repos.d 目录 ,备份原有repo,

修改CentOS7-Base-163.repo 名称为 CentOS-Base.repo

 (这一步不是必须的);

修改CentOS-Base.repo 内容 ,替换 $release 为 7 (单签centos版本);替换原有网址为163的网址:

完整内容如下 :

# CentOS-Base.repo
#
# The mirror system uses the connecting IP address of the client and the
# update status of each mirror to pick mirrors that are updated to and
# geographically close to the client.  You should use this for CentOS updates
# unless you are manually picking other mirrors.
#
# If the mirrorlist= does not work for you, as a fall back you can try the 
# remarked out baseurl= line instead.
#
#
[base]
name=CentOS-7 - Base - 163.com
#mirrorlist=http://mirrorlist.centos.org/?release=7&arch=$basearch&repo=os
baseurl=http://mirrors.163.com/centos/7/os/$basearch/
gpgcheck=1
gpgkey=http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-7

#released updates
[updates]
name=CentOS-7 - Updates - 163.com
#mirrorlist=http://mirrorlist.centos.org/?release=7&arch=$basearch&repo=updates
baseurl=http://mirrors.163.com/centos/7/updates/$basearch/
gpgcheck=1
gpgkey=http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-7

#additional packages that may be useful
[extras]
name=CentOS-7 - Extras - 163.com
#mirrorlist=http://mirrorlist.centos.org/?release=7&arch=$basearch&repo=extras
baseurl=http://mirrors.163.com/centos/7/extras/$basearch/
gpgcheck=1
gpgkey=http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-7

#additional packages that extend functionality of existing packages
[centosplus]
name=CentOS-7 - Plus - 163.com
baseurl=http://mirrors.163.com/centos/7/centosplus/$basearch/
gpgcheck=1
enabled=0
gpgkey=http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-7

5. yum update

运行makecache 生成缓存

yum makecache 

运行yum clean all

yum clean all

更新yum文件

yum update

yum update 过程中,可能会出现以下问题:

1. 发现 XX 个已存在的 RPM 数据库问题 :

1.首先yum clean all ,

2.安装 package-cleanup工具，有下面命令就不需要安装了，有的系统会自带

yum install yum-utils

然后更新一下仓库

package-cleanup --cleandupes

2. There are unfinished transactions remaining

1.安装 yum-complete-transaction（这是一个能发现未完成或被中断的yum事务的程序）

yum -y install yum-utils

2.清除yum缓存

yum clean all

3.运行 yum-complete-transaction,清理未完成事务

yum-complete-transaction --cleanup-only

3. conflicts with file from package

conflicts with file from package的问题导致软件安装失败。

需要使用如下命令解决

rpm -ivh --replacefiles xxxx.rpm

4. Rpmdb checksum is invalid: pkg checksums

RUN rpm --rebuilddb命令可以一条条修复rpm, 但是发现

执行 yum clean all , yum makecache 更加直接 .

ref:   https://www.cnblogs.com/DiZhang/p/12544744.html