Python升级

1.安装开发工具包，因为要编译安装Python

# yum -y group install "Development Tools" 

2.安装Python的依赖包，不安装依赖可能安装完成后没有pip3 软件。

# yum -y install openssl-devel bzip2-devel expat-devel gdbm-devel readline-devel sqlite-devel vim 

3.下载Python

# wget https://www.python.org/ftp/python/3.5.3/Python-3.5.3.tgz 

4.解压编译安装

# tar xf Python-3.5.3.tgz 
# cd Python-3.5.3
# ./configure --prefix=/usr/local/python3.5
# make
# make altinstall

5.为pip3和python3创建链接

# ln -fs /usr/local/python3.5/bin/python3 /usr/local/bin/
# ln -fs /usr/local/python3.5/bin/pip3 /usr/local/bin/
# mv /usr/bin/python/usr/bin/python_old
# ln -fs /usr/local/python3.5/bin/python3.5 /usr/bin/python
# ln -fs /usr/local/python3.5/bin/pip3.5 /usr/bin/pip

6.验证安装

# pip -V
pip 9.0.1 from /usr/local/python3.5/lib/python3.5/site-packages (python 3.5)
# python -V
Python 3.5.3

7.修改yum文件，否则yum将无法下载

vim /usr/bin/yum

将

#!/usr/bin/python

修改为

#!/usr/bin/python2.7

保存即可生效

注意：若遇到其他系统文件遇到语法错误，都需要像yum文件一样把python改为python2.7。例如/usr/libexec/urlgrabber-ext-down /usr/bin/firewall-cmd

参考：http://blog.youkuaiyun.com/tpc1990519/article/details/77856399