How to Enable X11 Forwarding on CentOS/RHEL 5,6,7

To enable X11 Forwarding on a server client edit the file “/etc/ssh/ssh_config” and on ssh server edit the file “/etc/ssh/sshd_config” and perform the following respective configuration changes.

For CentOS/RHEL 5,6

X11 Forwarding

Uncomment the line “# ForwardX11” and Change “ForwardX11 no” to “ForwardX11 yes”

ForwardX11 yes

Trusted X11 Forwarding

Uncomment the line “# ForwardX11Trusted” and Change “ForwardX11Trusted no” to “ForwardX11Trusted yes”

# If this option is set to yes then remote X11 clients will have full access
# to the original X11 display. As virtually no X11 client supports the untrusted
# mode correctly we set this to yes.
ForwardX11Trusted yes

3. After every change restart the sshd service or reboot the system.

# service sshd restart

Fro CentOS/RHEL 7

X11 Forwarding

1. Uncomment the following lines:

X11Forwarding yes
X11DisplayOffset 10
X11UseLocalhost no

2. Start and enable the sshd service

# systemctl start sshd.service
# systemctl enable sshd.service