X Forwarding for an Oracle DBA

Hi,

It’s been a long time. I want to write something about X Forwarding. you might feel more comfortable to use a GUI instead of silent installations sometimes. if you are connecting to a linux server remotely then you must enable X Forwarding to enable GUI for Oracle product like dbca, netca etc.

First of all, use MobaXterm to eliminate many problems. Moba sets some parameters for you and it also shows you if X Forwarding is enabled or disabled for that session:

just using MobaXterm is not enough of course:

1- create .Xauthority file under your linux user home directory:

touch ~/.Xauthority

2- check ssh config if X11Forwarding parameter is set to yes or not:

sudo vim /etc/ssh/sshd_config

it must be yes of course.

3- install xauth packages:

sudo yum install xorg-x11-xauth xorg-x11-utils xorg-x11-fonts-* xorg-x11-font-utils xorg-x11-fonts-Type1

(fonts are not mandatory)

4- create a magic cookie:

that is pretty much it. after these steps MobaXterm should be showing you X11Forwarding as enabled.

so far so good but there is a specific scenario. many company uses VPN accounts now and you are logging on to servers with your VPN account but oracle installation could be under another user like “oracle” and you might not have password of oracle user since it is also a directory user and managed by different teams on hosting company (or your own company). in that case you might be using “sudo su – oracle” command to switch to oracle user and if you do that X11 Forwarding will not work! as a quick hack you can use this:

my vpn user: mustafa

oracle installation user: oracle

login as mustafa, then copy .Xauthority file to oracle user’s home directory, then change owner of the .Xauthority file as oracle:

you can put this into a sh file and run. you must run these commands with sudo of course.

last step is $DISPLAY parameter. echo $DISPLAY parameter with mustafa user and after switching to oracle user set this parameter:

that’s it. you should be able to use X11 Forwarding.

hope this helps.

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