######卸载Centos自带的git1.7.1:

通过 git –version 查看系统带的版本，Cento6.5应该自带的是git版本是1.7.1

yum remove git

######下载git2.2.1并将git添加到环境变量中

wget https://github.com/git/git/archive/v2.2.1.tar.gz
tar zxvf v2.2.1.tar.gz
cd git-2.2.1
make configure 
./configure --prefix=/usr/local/git --with-iconv=/usr/local/libiconv
make all doc
make install install-doc install-html
echo "export PATH=$PATH:/usr/local/git/bin" >> /etc/profile
source /etc/profile

######查看版本号

git --version

Q.E.D.