方法一： https://或者http://替换成git://

方法二： 1. Failed connect to github.com:443； Connection refused

• 可能是DNS解析污染导致无法获取正确的IP

• 查找IP方法： 打开https://websites.ipaddress.com/github.com

• 添加hosts

cat >>/etc/hosts <<EOF
140.82.113.3   github.com
EOF

2. TCP connection reset by peer

• git版本过低导致

• 更新git版本

  wget https://mirrors.edge.kernel.org/pub/software/scm/git/git-2.9.5.tar.gz
  yum -y install gcc
  tar xf git-2.9.5.tar.gz
  mkdir -p /soft/git 
  cd git-2.9.5
  ./configure --prefix=/soft/git 
  

• 安装

  yum -y install zlib-devel
  yum install -y openssl-devel.x86_64
  yum install -y libcurl-devel.x86_64
  yum install -y expat-devel.x86_64
  
  make && make install
  

• 若安装出现错误

  yum install perl-ExtUtils-MakeMaker package
  

• 设置环境变量

  vim /etc/profile
  export PATH=/soft/git/bin:$PATH
  

• 保存

  source /etc/profile