centos7.4出現yum command not found

購買的雲服務器運行yum命令出現yum command not found。

經過將雲主機自帶的yum和python卸載掉，而且同時須要關注/usr/bin/yum文件的首行解釋。我定義其爲"#!/usr/bin/python"

1.卸載python:

1 rpm -qa|grep python|xargs rpm -e --allmatches --nodeps 2 whereis python|xargs rm -fr

2.卸載yum:

1 rpm -qa|grep yum|xargs rpm -e --allmatches --nodeps 2 rm -rf /etc/yum.repos.d/*
3 whereis yum|xargs rm -fr

3.建立目錄python和yum用以存放rpm包：

1 mkdir /usr/local/src/python
2 mkdir /usr/local/src/yum

4.使用wget分別下載python以及yum的rpm包（注意：必定要和系統的版本號對應）

    （1）下載python的rpm包：

1 #cd /usr/local/src/python 進入目錄 2 
3 #wget http://vault.centos.org/7.2.1511/os/x86_64/Packages/python-2.7.5-34.el7.x86_64.rpm
4 #wget http://vault.centos.org/7.2.1511/os/x86_64/Packages/python-iniparse-0.4-9.el7.noarch.rpm
5 #wget http://vault.centos.org/7.2.1511/os/x86_64/Packages/python-pycurl-7.19.0-17.el7.x86_64.rpm
6 #wget http://vault.centos.org/7.2.1511/os/x86_64/Packages/python-devel-2.7.5-34.el7.x86_64.rpm
7 #wget http://vault.centos.org/7.2.1511/os/x86_64/Packages/python-libs-2.7.5-34.el7.x86_64.rpm
8 #wget http://vault.centos.org/7.2.1511/os/x86_64/Packages/python-urlgrabber-3.10-7.el7.noarch.rpm
9 #wget http://vault.centos.org/7.2.1511/os/x86_64/Packages/rpm-python-4.11.3-17.el7.x86_64.rpm

    （2）下載yum的rpm包：

1 #cd /usr/local/src/yum 
2 
3 #wget http://vault.centos.org/7.2.1511/os/x86_64/Packages/yum-3.4.3-132.el7.centos.0.1.noarch.rpm
4 #wget http://vault.centos.org/7.2.1511/os/x86_64/Packages/yum-metadata-parser-1.1.4-10.el7.x86_64.rpm
5 #wget http://vault.centos.org/7.2.1511/os/x86_64/Packages/yum-plugin-fastestmirror-1.1.31-34.el7.noarch.rpm

 

5.安裝python以及yum的rpm包

（1）安裝python:

1 #cd /usr/local/src/python 2 
3 #rpm -ivh python-* rpm-python-* 
4  出現安裝包的依賴問題，此時以下解決便可： 5 
6 #rpm -ivh python-* rpm-python-* --nodeps --force 7             --nodeps --force爲不考慮依賴包，強制安裝。 8 
9             安裝完後便可運行python:

 （2）安裝yum:

1 #cd /usr/local/src/yum 
2 #rpm -ivh yum-*