Thursday, February 24, 2011

Load: Class VncViewer.class not found

Hi Friends,

The other day I started to play around Oracle's new Virtualization product Oracle VM 2.2. Its pretty neat product with quick installation & no much hiccups.

The interesting part starts once you have Oracle VM Manager, the web-based tool to manage & deploy Guest VMs on the Oracle VM Server.

Since the entire offering is based out of Xen's Hypervisor & linux based, the remote console facility is leveraged using VNC.

If you already have deployed a new Guest VM using Oracle VM Manager and try to view its console, you will get an error as in the Java Applet Execution window.

Load: Class VncViewer.class not found

The simple reason being is the VncViewer.jar is missing due to which it fails to invoke VNC Viewer within the browser.  

To install follow below quick steps:

1) Get TightVNC RPM:
bash$ wget http://oss.oracle.com/oraclevm/manager/RPMS/tightvnc-java-1.3.9-3.noarch.rpm
2) Install the new downloaded RPM
bash$ rpm -ivh tightvnc-java-1.3.9-3.noarch.rpm

Once done verify if the VncViewer.jar file is created successfully under
/opt/oc4j/j2ee/home/applications/OVS/webapp1/Class

Thats it!
Restart your browser and login into Oracle VM Manager again to browse to the console successfully :-)

Keywords:
Oracle VM Server, Oracle VM Manager, Xen, Virtualization, Vmware, etc.
 

Thursday, January 13, 2011

How to edit /etc/sudoers?

Hi Friends,

Well you must have come across various situations when you need to quickly edit the /etc/sudoers file for making changes.

Though it is not straight forward to open in an vi editor & edit it, below are time saving commands for Linux & Unix to quickly edit the same:

Linux:
bash-3.00$ sudo visudo

Unix:
bash-3.00$ /usr/local/bin/sudo /usr/local/sbin/visudo

VISUDO opens the /etc/sudoers file in a temporary editable mode, which can be changed and saved to reflect changes immediately.

Hope this tip helps :-)

Keywords:
Linux, Unix, Red Hat, Solaris, /etc/sudoers, vi, visduo, sudo, edit, etc