Disable and Enable IPV6 in RHEL

Disable and Enable IPV6 in RHEL

Release:

RedHat Enterprise Linux 5

Problem:

Need to disable the IPV6 in RedHat Enterprise Linux

Solution:

Disable IPV6 in RHEL:

1)      Add the below line in the modprobe.conf file

            # vi /etc/modprobe.conf

            alias net-pf-10 off

            alias ipv6 off                    # Add this for RHEL before 5.4

            options ipv6 disable=1    # Add this for 5.4 and later

Note : If any entry available like “alias net-pf-10 ipv6”, delete that entry.

2)      Also add the below entry in the network file to prevent error

            # vi /etc/sysconfig/network

            NETWORKING_IPV6=no

3)      Reboot the server to disable the IPV6

      # shutdown -r now

Enable IPV6 in RHEL:

4)      Add the below entry in the modprobe.conf file

      # vi /etc/modprobe.conf

      alias net-pf-10 ipv6

Note : Remove if any entry like “alias net-pf-10 off or alias ipv6 off or options ipv6 disable=1” in the modprobe.conf file.

5)      Change the “ NETWORKING_IPV6” parameter value to yes in the netwok file.

      # vi /etc/sysconfig/network

      NETWORKING_IPV6=yes

6)      Restart the server to enable the IPV6 support

            # shutdown -r now

Enable XDMCP in Linux

Enable XDMCP in Linux

Release:

RedHat Enterprise Linux 5

SUSE Linux 10

Problem:

Need to enable the xdmcp protocol in the Linux server for getting remote using XBrowser.

Solution:

In RHEL Server:

1)      Install the gdm package

# yum install gdm

2)      Enable the xdmcp protocol by adding the below entries in the custom.conf file.

# vi /etc/gdm/custom.conf

[security]

AllowRemoteRoot=true

DisallowTCP=false

[xdmcp]

Enable=true

Note: Here “AllowRemoteRoot=true” used to allow root access.

3)      Restart the gdm service

# gdm-restart

4)      Check weather xdmcp port is opened or not, using netstat command

# netstat –an | grep 177

udp        0      0 0.0.0.0:177         0.0.0.0:*  

In SUSE Server:

5)      Install the required 2 packages

# yum install gdm xorg-x11

6)      Set the default display manager by editing the displaymanager file

# vi /etc/sysconfig/displaymanager

DISPLAYMANAGER="gdm"

DISPLAYMANAGER_REMOTE_ACCESS="yes"

7)      Enable the xdmcp protocol by editing the gdm.conf file

# vi /etc/opt/gnome/gdm/gdm.conf

[security]

AllowRoot=true

AllowRemoteRoot=true

[xdmcp]

Enable=true

8)      To make xdmcp listening on xdm by edit the xdm-config file

# vi /etc/X11/xdm/xdm-config

!DisplayManager.requestPort:    0

Note: Comment out this line for xdmcp listen on xdm

9)      Restart the service and check with netstat

# rcxdm restart

# netstat –an | grep 177

udp        0      0 0.0.0.0:177             0.0.0.0:*

10)   Verify from the Windows client using Xbrowser as root.