X11 Setup with SSH Linux

PROCESS OVERVIEW:

In order to obtain the ability to interact with an X11 GUI remotely, we will follow these general steps:

1. Ensure that the foundational X11 packages are installed
2. Ensure that OpenSSH server is configured to forward X11 connections
3. Configure a local X11 server on our workstation (You can use MobaXterm too)
4. Configure our ssh application to forward X11 requests ( I'll use MobaXterm, however, Xming can also be installed at local machine.)
5. Test with a simple application
6. Configured authentication if user changes are needed.

1. # yum install xorg-x11-xauth xterm xorg-x11-apps -y

2. # cat /etc/ssh/sshd_config | grep -i X11
X11Forwarding yes
X11DisplayOffset 10
X11UseLocalhost no

# service sshd restart

Redirecting to /bin/systemctl restart sshd.service

3. Xming  or MobaXterm need to be installed on the workstation.

4. Try to connect the server by mentioning the hostname on MobaXterm. However, for putty you need to check "X11 forwarding" under SSH settings.

5# /usr/bin/xauth

Using authority file /root/.Xauthority

xauth> exit

#xclock

#xeyes

From Putty: We need to set the display as below:

# xauth list

server:10  MIT-MAGIC-COOKIE-1  5a5f2e0832b24f8c3391614cec512363

# export DISPLAY=server:10

# xclock

Warning: Missing charsets in String to FontSet conversion

6. Suppose We need to run the X11 for a particular user - webadmin

[root@server~]# su - webadmin

Last login: Mon Sep  9 14:59:35 IST 2019 from vp-1c2oadc062.1dc.com on pts/0

[webadmin@server~]$ xclock

Error: Can't open display:

[webadmin@server~]$ xauth list

xauth:  file /home/webadmin/.Xauthority does not exist

# cp .Xauthority /home/webadmin/  (from root)
#chown webadmin:webadmin /home/webadmin/.Xauthority (from root)

#[webadmin@server~]$ xauth

Using authority file /home/webadmin/.Xauthority

xauth> exit

[webadmin@server~]$ xauth list

server:10  MIT-MAGIC-COOKIE-1  8d2414ef1216a5ef3b276866c490311c

export DISPLAY=server:10

[webadmin@lipvap1077 ~]$ xclock

Warning: Missing charsets in String to FontSet conversion

[webadmin@lipvap1077 ~]$