RHEL7 默认是最小化安装（Minimal Install），没有图形界面，
我们应该选择Server with GUI。若已错过此步骤，我们采用以下方式补充安装GUI界面。

先配置yum源
可以参考我的这篇文章
http://blog.itpub.net/27771627/viewspace-1223153/

[root@LiuZhenmnt]# rpm --import RPM-GPG-KEY-redhat-release

执行以下命令

[root@LiuZhenmnt]# yum group list

Loaded plugins:langpacks, product-id, subscription-manager

This system is notregistered to Red Hat Subscription Management. You can use subscription-managerto register.

There is no installedgroups file.

Maybe run: yum groupsmark convert (see man yum)

Available environmentgroups:

   Minimal Install

   Infrastructure Server

   File and Print Server

   Basic Web Server

   Virtualization Host

   Server with GUI

Available Groups:

   Compatibility Libraries

   Console Internet Tools

   Development Tools

   Graphical Administration Tools

   Legacy UNIX Compatibility

   Scientific Support

   Security Tools

   Smart Card Support

   System Administration Tools

   System Management

Done

[root@LiuZhen mnt]#

 列出的组包中 Server with GUI 就是安装图形所需要的，继续执行以下命令

[root@LiuZhenmnt]# yum -y groupinstall "Server with GUI"

Loaded plugins:langpacks, product-id, subscription-manager

This system is notregistered to Red Hat Subscription Management. You can use subscription-managerto register.

There is no installedgroups file.

Maybe run: yum groupsmark convert (see man yum)

Package1:NetworkManager-config-server-0.9.9.1-12.git20140326.4dba720.el7.x86_64already installed and latest version

Warning: Group coredoes not have any packages to install.

Warning: Groupgnome-desktop does not have any packages to install.

Warning: Groupguest-agents does not have any packages to install.

Packagegtk2-immodule-xim-2.24.22-5.el7.x86_64 already installed and latest version

Packageimsettings-gsettings-1.6.3-9.el7.x86_64 already installed and latest version

Packageibus-gtk3-1.5.3-11.el7.x86_64 already installed and latest version

Packageibus-gtk2-1.5.3-11.el7.x86_64 already installed and latest version

Packagegtk3-immodule-xim-3.8.8-5.el7.x86_64 already installed and latest version

Warning: Groupinput-methods does not have any packages to install.

Group input-methodsdoes have 2 conditional packages, which may get installed.

Warning: Groupguest-desktop-agents does not have any packages to install.

Warning: Group fontsdoes not have any packages to install.

Warning: Groupprint-client does not have any packages to install.

Warning: Groupdesktop-debugging does not have any packages to install.

Warning: Groupdial-up does not have any packages to install.

Warning: Group basedoes not have any packages to install.

Group base does have1 conditional packages, which may get installed.

Packagegstreamer1-plugins-bad-free-1.0.7-4.el7.x86_64 already installed and latestversion

Packagegstreamer1-plugins-good-1.0.7-5.el7.x86_64 already installed and latest version

Warning: Groupmultimedia does not have any packages to install.

Warning: Groupinternet-browser does not have any packages to install.

Warning: Group x11does not have any packages to install.

Maybe run: yum groupsmark install (see man yum)

No packages in anyrequested group available to install or update

[root@LiuZhenmnt]# show-installed

WARNING: Thefollowing packages are installed but not in the repository:

cups-pdf

WARNING: Thefollowing groups contain packages not found in the repositories:

XXX base

yum-plugin-security

XXX core

ql2100-firmware

ql23xx-firmware

ql2200-firmware

bfa-firmware

XXX gnome-desktop

unoconv

polkit-gnome

gvfs-obexftp

@base

-yum-plugin-security

@core

-bfa-firmware

-ql2100-firmware

-ql2200-firmware

-ql23xx-firmware

@dial-up

@fonts

@gnome-desktop

-gvfs-obexftp

-polkit-gnome

-unoconv

@guest-agents

@guest-desktop-agents

@input-methods

@internet-browser

@multimedia

@print-client

@x11

# Others

Red_Hat_Enterprise_Linux-Release_Notes-7-zh-CN

Red_Hat_Enterprise_Linux-Release_Notes-7-zh-TW

clucene-core

cups-pdf

grub2

lftp

samba-client

screen

# 1196 package names,228 leaves

# 12 groups, 8leftovers, 8 excludes

# 32 lines

可以执行startx看下效果。

来源：http://blog.itpub.net/27771627/viewspace-1223155/