redhat3 4 5 6 xmanager

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红帽3 红帽4
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1 /etc/inittab
id：3：initdefault
改为如下，如果原来就是id：5：initdefault就不用更改。

(可选)
x：5：respawn：/etc/X11/prefdm -nodaemon
将它修改为x：5：respawn：/usr/bin/gdm

2 /etc/X11/gdm/gdm.conf
[xdmcp]
Enable=true
Port=177
DisplayPerHost=9

3 /etc/X11/xdm/Xaccess
* #any host can get a login window

4 /etc/X11/xdm/xdm-config
！DisplayManager.requestPort： 0

5 chmod /etc/X11/xdm/Xservers的属性为444，/etc/X11/xdm/Xsetup_0的属性为755.

最后，如果我们的Linux机器配置有防火墙
iptables -A INPUT -p udp -s 0/0 -d 0/0 ——dport 177 -j ACCEPT

可选
/etc/X11/xdm/kdmrc
/usr/share/config/kdm/kdmrc
或
/etc/opt/kde2/share/config/kdm/kdmrc
根据你的操作系统不同而打开不同的文件
找到[xdmcp]部分，
修改 Enable为true。

6 重新启动Linux.

? 其实不用重启系统
操作步骤如下：
1. $ su - 成为root用户
2. 杀掉/usr/X11R6/bin/X进程，系统会重启X进程
# kill `ps -ef|grep -v grep|grep "/usr/X11R6/bin/X" |awk '{print $2}'`
3. 发SIGHUP或SIGUSR1信号给gdm守护进程
# kill -USR1 `cat /var/run/gdm.pid`

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Red Hat Enterprise Linux 5
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/etc/inittab
启动级别5
x:5:respawn:/usr/sbin/gdm

vi /usr/share/gdm/defaults.conf
[security]
AllowRoot=true
AllowRemoteRoot=true

[xdmcp]
Enable=true
DisplaysPerHost=10
Port=177

/etc/gdm/custom.conf
[xdmcp]
Enable=true

[security]
DisallowTCP=false
AllowRemoteRoot=true

Next, restart X Windows:
[root@racdb2 ~]# init 3
[root@racdb2 ~]# init 5
[root@racdb2 ~]# /usr/sbin/gdm-restart

You can test the GDM login screen locally using the following:
[root@racdb2 ~]# X -query localhost :1

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Red hat Enterprise Linux 6
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1. vi /etc/gdm/custom.conf
[security]
DisallowTCP=false

[xdmcp]
Enable=true ;其实只添加这行也可以
Port=177

2. Add UDP port 177 to the Allow list on firewall.
防火墙关闭的就不用修改
/etc/sysconfig/ipchains文件中加入以下语句：
-A input -p udp -s 0/0 -d 0/0 177 -j accept

3. As an admin, do 'init 3' and then, 'init 5'
修改/etc/inittab，将
id:3:initdefault:
修改为：
id:5:initdefault:

If you have enabled XDMCP and open UDP 177 on the server
, make sure gdm is running.
Use 'ps -aef | grep dm' and it should give you the display manager
that is running on the server.
If it it not running, please make sure the display manager
such as gdm or kdm is installed on the machine.
Red Hat 6 does not install display manager by default.