This post describes preparing an X11 graphical display system on a Linux 7 compute instance running on Oracle Cloud Infrastructure (OCI). A graphical interface is the default method of using the Oracle Analytics Cloud (OAC) Remote Data Gateway (RDG) installer. This post is also useful for preparing the 1.5 version of Remote Data Connector.
X11 is the simplest graphical display system to provision in a compute instance. Other options include installing a VNC server or a full desktop environment such as GNOME or KDE.
It also describes configuring an X11 server running on a MAC-OS or Windows client to display a graphical user interface (GUI).
This post is not intended for those who currently have a Linux environment with a Graphical Display system available for RDG.
July 22, 2020 for OAC 5.7
May 19, 2020 for OAC 5.6
March 26, 2020 for RDG 105.5
October 15, 2019 for RDG 105.4
June 28, 2019 for RDG 105.3
Before you Begin
Preparing the X11 Graphical Display System
Preparing the X11 Server
Validating the Graphical User Interface
Preparing Ports for RDC and RDG
In this post, the term "instance" refers to the Linux compute instance hosting a RDG agent.
Preparing the graphical user interface for RDG requires the following:
The IP address or host name of the compute instance.
The SSH private key associated with the instance's public key.
A SSH utility with X11 tunneling capability to access the instance.
Administration privileges on a MAC-OS or Windows client.
Follow the steps in Preparing SSH Tunneling for Oracle Analytics Cloud Remote Data Gateway in a Private Subnet to configure your SSH client to access the RDG host publicly or privately via a bastion host.
This section describes configuring an X11 graphical display system for the RDG Linux installer. It assumes the SSH client config file has an entry named RDG-HOST.
ssh RDG-HOST sudo cp /etc/ssh/sshd_config /etc/ssh/sshd_config.orig
Set the X11UseLocalHost parameter for correct creation of the DISPLAY environment variable. Edit the sshd_config file, uncomment the X11UseLocalHost parameter and change the value from yes to no.
Copy the configuration file down to your client, edit it using a local editor e.g. Notepad, TextEdit and copy the file back to the server.
ssh RDG-HOST touch sshd_config
ssh RDG-HOST sudo cp /etc/ssh/sshd_config /home/opc
scp RDG-HOST:sshd_config ~
scp ~/sshd_config RDG-HOST:/home/opc
Copy the file back to original location owned by root.
ssh RDG-HOST sudo cp /home/opc/sshd_config /etc/ssh
sudo vi /etc/ssh/sshd_config
Save the file and exit the vi editor.
ssh RDG-HOST sudo systemctl restart sshd
This is accomplished by installing the xauth application.
ssh RDG-HOST sudo yum -y install xauth
The xterm application may be used to open an X11 terminal on a user's client machine. This post uses it to validate the graphical user interface.
ssh RDG-HOST sudo yum -y install xterm
This library is required for the RDG installer.
ssh RDG-HOST sudo yum -y install libXtst.x86_64
This post uses MAC-OS and XQuartz.
Download the XQuartz .dmg file and install it using the default values.
Also required is an SSH client that supports X11 tunneling. For MAC-OS the terminal application is sufficient. For Windows, PuTTY is the most widely used: https://www.putty.org
This post uses MAC-OS and the terminal application.
The configuration is validated by starting the X11 Server on the MAC-OS. This is done by starting the XQuartz application.
Use Finder to open the Applications>Utilities folder and double-click XQuartz. An xterm window opens on the MAC.
Now this terminal session or another remote terminal session can be used to SSH into the Linux instance to run an X11 application.
Use the SSH utility with the -X option to set up an X11 tunnel session on the Linux instance and run the Linux xterm application.
ssh -Y RDG-HOST xterm &
You may have to wait up to a minute, then a new Xterm window appears on your desktop from the Linux instance validating the configuration.
You can now proceed to install and configure an OAC Remote Data Gateway agent on a Linux compute instance.
This post described preparing an X11 graphical display system on a Linux 7 compute instance running on Oracle Cloud Infrastructure and an X11 server running on a MAC-OS client to display an X11 graphical user interface (GUI).
For other posts relating to analytics and data integration visit http://www.ateam-oracle.com/dayne-carley.