1.oracle安装报错如下：

Checking Temp space: must be greater than 120 MB.   Actual 109499 MB    Passed

Checking swap space: must be greater than 150 MB.   Actual 8191 MB    Passed

Checking monitor: must be configured to display at least 256 colors

>>> Could not execute auto check for display colors using command /usr/bin/xdpyinfo. Check if the DISPLAY variable is set.    Failed <<<<

Some requirement checks failed. You must fulfill these requirements before

continuing with the installation,

Continue? (y/n) [n] Y

>>> Ignoring required pre-requisite failures. Continuing...

Preparing to launch Oracle Universal Installer from /tmp/OraInstall2016-12-23_03-55-53PM. Please wait ...

DISPLAY not set. Please set the DISPLAY and try again.

No protocol specified

Exception in thread "main" java.lang.NoClassDefFoundError

at java.lang.Class.forName0(Native Method)

at java.lang.Class.forName(Class.java:164)

at java.awt.Toolkit$2.run(Toolkit.java:821)

at java.security.AccessController.doPrivileged(Native Method)

at java.awt.Toolkit.getDefaultToolkit(Toolkit.java:804)

at com.jgoodies.looks.LookUtils.isLowResolution(LookUtils.java:484)

at com.jgoodies.looks.LookUtils.(LookUtils.java:249)

at com.jgoodies.looks.plastic.PlasticLookAndFeel.(PlasticLookAndFeel.java:135)

at java.lang.Class.forName0(Native Method)

at java.lang.Class.forName(Class.java:242)

at javax.swing.SwingUtilities.loadSystemClass(SwingUtilities.java:1779)

at javax.swing.UIManager.setLookAndFeel(UIManager.java:453)

at oracle.install.commons.util.Application.startup(Application.java:780)

at oracle.install.commons.flow.FlowApplication.startup(FlowApplication.java:165)

at oracle.install.commons.flow.FlowApplication.startup(FlowApplication.java:182)

at oracle.install.commons.base.driver.common.Installer.startup(Installer.java:348)

at oracle.install.ivw.db.driver.DBInstaller.startup(DBInstaller.java:124)

at oracle.install.ivw.db.driver.DBInstaller.main(DBInstaller.java:155)

2.解决办法

Depending on the Unix Shell, you can use one of the following commands as examples to set the DISPLAY environment variable:

- For csh:  % setenv DISPLAY 192.168.1.128:0.0

- For sh, ksh and bash: $ DISPLAY=192.168.1.128:0.0; export DISPLAY

Use the following command to see what shell is being used:

echo $SHELL

Use the following command to view the current DISPLAY environment variable setting:

echo $DISPLAY

- Make sure that client users are authorized to connect to the X Server.

To enable client users to access the X Server, open an xterm, dtterm or xconsole as the user that started the session and type the following command:

% xhost +

To test that the DISPLAY environment variable is set correctly, run a X11 based program that comes with the native operating system such as 'xclock':

%

If you are not able to run xclock successfully, please refer to your PC-X Server or OS vendor for further assistance.

Typical path for xclock: /usr/X11R6/bin/xclock

3.总结：看上面英文，提示是因为当前用户oracle没有授权使用X Server.需要授权。如下解决办法：

以root登录,执行命令xhost  +  .

# su - root

#xhost +

access control disabled,clients can connect from any host

#su - oracle

$./runInstall可以

网上也有解决办法，说图形界面不是用oracle用户登录，所以报上面错误。但是我用oracle用户登录(我是gnome，用vncserver图形界面)，安装oracle还是报上面display错误。其实问题根本原因是：当前用户oracle没有授权使用X Server.需要授权。

4.如何设置DISPLAY?找出当前display?

以root用户登录,输入命令xdpyinfo，记录下里面的name of display：后的字符串，如 name of display：127.0.0.1：1.0，找到当前登录的display信息，然后使用命令：export DISPLAY=:2.0

5.如何授权所有用户都可以访问该display?

在执行xhost +命令(使得所有客户都可以访问)

返回信息为： access control disabled,clients can connect from any host

如果xhost +不能执行，可以输入命令export DISPLAY=:0执行一下

再执行xhost +

xhost + ip (name表示那个ip机器可以使用该服务)

6.在oracle静默安装的时候，出现上面问题：centos7静默安装oracle11gR2 64位报错java.lang.NoClassDefFoundError？

参见我的文章：http://blog.itpub.net/30393770/viewspace-1825067/

来自 “ ITPUB博客 ” ，链接：http://blog.itpub.net/30393770/viewspace-2131284/，如需转载，请注明出处，否则将追究法律责任。