使用gitlab官网给的源码进行安装，步骤如下：
Install a GitLab CE Omnibus package on
CentOS 6 (and RedHat/Oracle/Scientific Linux 6)
Check if your server meets the hardware requirements. GitLab packages are built for 64bit systems. For 32bit OS, consider alternative installation methods.
1. Install and configure the necessary dependencies
If you install Postfix to send email please select 'Internet Site' during setup. Instead of using Postfix you can also use Sendmail or configure a custom SMTP server. If you wish to use Exim, please configure it as an SMTP server.
On Centos 6 and 7, the commands below will also open HTTP and SSH access in the system firewall.
sudo yum install curl openssh-server openssh-clients postfix cronie
sudo service postfix start
sudo chkconfig postfix on
sudo lokkit -s http -s ssh
2. Add the GitLab package server and install the package
curl -sS https://packages.gitlab.com/install/repositories/gitlab/gitlab-ce/script.rpm.sh | sudo bash
sudo yum install gitlab-ce #在安装过程中，如果哦网速比较好的话，会很快安装成功，如果不好，会中途断断续续的，安装失败后，在哪里失败，哪里重新安装。
3. Configure and start GitLab
sudo gitlab-ctl reconfigure
4. Browse to the hostname and login
Username: root
Password: 5iveL!fe