in Oracle

Running GUI application as another (non-root) user – Netmgr


I can open the Netmgr in the Xshell through Xmanager without any issue. There was problem to do so using Oracle user under xWindows. Resolved it by setting “DISPLAY=:0.0”.


Need to use Netmgr GUI in xWindows. Error as below,

[tom@ocp ~]$ netmgr
****DISPLAY environment variable not set!
    Oracle Net Manager is a GUI tool which
    requires that DISPLAY specify a location
    where GUI tools can display.
    Set and export DISPLAY, then re-run.

After setting below,

[tom@ocp ~]export DISPLAY=:0.0

Had below error,

[tom@ocp ~]$ netmgr
    at oracle.ewt.lwAWT.BufferedApplet.<init>(Unknown Source)
    at oracle.sysman.emSDK.client.appContainer.WebApplication.</init><init>(
    at</init><init>(Unknown Source)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(
    at java.lang.reflect.Constructor.newInstance(
    at java.lang.Class.newInstance0(
    at java.lang.Class.newInstance(
    at oracle.sysman.emSDK.client.appContainer.WebApplication.main(


The problem is normal Oracle user doesn’t have the same priviledge as root to use GUI, this issue can be resolved by below command.

[root@ocp Desktop]# xhost +
access control disabled, clients can connect from any host
[root@ocp Desktop]# DISPLAY=:0.0
[root@ocp Desktop]# export DISPLAY
[root@ocp Desktop]# xhost +
access control disabled, clients can connect from any host
[root@ocp Desktop]# su - tom  #tom is the normal Oracle user.
Last login: Sun Dec 23 10:35:02 SGT 2018 on pts/4
[tom@ocp ~]$ DISPLAY=:0.0
[tom@ocp ~]$ export DISPLAY
[tom@ocp ~]$ netmgr
[tom@ocp ~]$ 

The command xhost + meaning is as below,

+       Access is granted to everyone, even if they aren't on the list (i.e., access control is turned off).



Running GUI application as another (non-root) user