Tag Archives: Linux

Centos 6.2 with Firefox 9 and Google Chrome 16

Centos recently published v6.2


Out of the box is Firefox 3.x and no Google Chrome installed.

Steps to install Google Chrome 16 (as root)

Steps to install Firefox 9 (as before as root).

To install the Virtual box Guest Additions:

  1. yum update
  2. yum install gcc
  3. yum install kernel-devel
  4. Mount Guest Additions iso image
  5. Run autostart on the cd
  6. Enter root password
  7. After install reboot vm


Canon LBP6650 under Ubuntu 11.04

Canon provide Debian Packages to install the driver under ubuntu for download. Offical supported is only the previous version 10.04 of ubuntu. Extracting the zip file you will find under


the deb packages. First thing to install is cndrvcups-common_2.20-l_i386.deb with dpkg -i <deb file>. The problem is that ubuntu 11.04 doesn’t contain the required gs-esp package.

Workaround is to download and install it with

dpgk -i gs-esp_9.01~dfsg~svn12047-0ubuntu1_all.deb

After that you can install the common canon driver and afterwards the ufr driver:

dpgk -i cndrvcups-common_2.20-1_i386.deb dpgk -i cndrvcups-ufr2-uk_2.20-1_i386.deb

Now you can open the driver setup application and click on the add button. Choose network printer, enter the ip of your canon printer and click on examine. Select from the list below Canon and click on next. Select “LBP6650” and click on next. Confirm dialog with use button. Test your configuration with printing a test page.

Printing via SMB from Ubuntu 10.04 to Windows 7

I have successfully installed Ubuntu 10.04 Beta 1 on my Samsung NC10 with dual boot side by side to windows XP Home. The installation process is very smart and allow you to import settings like desktop background from the installed windows xp home. Printer configuration was a bit complicated. The first thing is to change the workgroup definition in


workgroup = XYZ

Change XYZ to your windows 7 workgroup name. Next step is to uninstall the “Windows Live Sign-In Assistant” under windows 7 which is the main cause why the windows shares like the printers are not available from ubuntu. After that go to menu item System => administration => Printer. Click on add button and select from the list under network printer the last entry “windows printer via SAMBA”. When you now click on browse will be your workgroup and below your windows 7 pc with the printer shares be available.

Tomcat 6 Problems on Ubuntu 9.10

The default behavior of the tomcat6 server installed from the ubuntu repository is to forbid any read operation of System.getProperty(). I used tomcat6 as deployment target for the hudson builds on the same machine. AspectJ is used in a sample Spring 3 REST application. Tomcat6 logs (catalina-…log) shows the following exception

Caused by: java.security.AccessControlException: access denied (java.util.PropertyPermission org.aspectj.tracing.debug read)
        at java.security.AccessControlContext.checkPermission(AccessControlContext.java:323)
        at java.security.AccessController.checkPermission(AccessController.java:546)
        at java.lang.SecurityManager.checkPermission(SecurityManager.java:532)
        at java.lang.SecurityManager.checkPropertyAccess(SecurityManager.java:1285)
        at java.lang.System.getProperty(System.java:686)
        at org.aspectj.weaver.tools.TraceFactory.getBoolean(TraceFactory.java:34)
        at org.aspectj.weaver.tools.TraceFactory.(TraceFactory.java:21)
        ... 68 more

Updating aspectj in the maven pom to the latest version 1.6.8 doesn’t solve
the problem. The same war file works under windows with tomcat 6.0.24 without any problems. An Forum entry shows the right hint. Inside the init script
/etc/init.d/tomcat6 is default TOMCAT_SECURITY set to true, which forces the /etc/tomcat6/policy.d/* policies to be used in every web
application inside tomcat.

# Use the Java security manager? (yes/no)

So the solution can be quick (set the TOMCAT_SECURITY property inside the init script to no) or a bit more complicated (set a new policy for your web application as new file inside the policy.d folder). The problem with the more complicated one is that you need to know every security relevant operation to write the policy file).

Damn Small Screen

I switched recently on my home server from OpenSuse 10.3 to Ubuntu Hardy Heron 8.0.4. Main reason was the package management with zypper as backend. Each Distro use several Software Repositories with RPMs where you can search for new software to install on your machine. Normally between four to eight repo’s are configured independent which distro you use. OpenSuse become more and more a pain in my ass. Main reason was the more and more increasing time which yast needs to show me the available software packages. For a test drive is VMWare Server really nice. Just setup a new VM, install a distro inside and see if it fits your needs.

Under Ubuntu you must first decide if you want the desktop or server edition. On my notebook was the primary requirement to have a back end for application server like Archiva or Nexus. Both very comfortable maven proxies with a web frontend. So i decided to install the server edition. The server edition have no window manager and starts a linux just with a console login. So far so good. A little bit hidden is the possibility to change the default screen solution from 800×600 to a larger one. Scrolling log or config files is not that pretty under such conditions.

The solution is in the /etc/grub/menu.1st file. In the end of the file is a list of linux versions. Each runnable linux configuration has a title, root, kernel and initrd line. For a 1024×768 you can append to the kernel line


according to this howto. Ubuntu has in the last weeks published a new service pack called 8.04.1. Normal updated are installed with a “apt-get update” followed by “apt-get upgrade” to install updates for installed packages. I saw messages about retained packages after the availibity of this new service pack. A “apt-get dist-upgrade” forces to install the retained packages including a new kernel. Remember the line with the kernel paramater in the grub menu file. The update updates this file as well. Grateful it notice my changes and ask me what to do. My first intention was to say ok overwrite my changes and i add that vga parameter as well. That works but it can be handled much smarter. Linux kernel updates can be happen more often.

The solution is to add the vga parameter to defoptions line instead of the kernel line. This line is normally uncommented with a leading # character. So add this line


This 0x317 is the hex definition. Also possible is to write vga=719 with decimal notation.