Friday, 14 October 2011

Mac OS X new installed applications shown "* is an application downloaded from the Internet"

In the quite normal situation, after a new application is downloaded from the Internet and is run for the first time, a warning message is shown: " * is an application downloaded from the Internet. Are you sure you want to open it?".  Actually, after you answer it with a yes. this message shouldn't appear anymore in the following starting up the application. This is the normal case!!!

Let's start a strange one: the warm warning message consistently appear in every times' start up process of some specific application. I believe that this is caused by an inappropriate installation of the application. The main point is that how to get ride of the message!!!

xattr -d -r com.apple.quarantine /Path/to/application/

this should be run in a super user mode.


reference: osxdaily.com/2010/09/12/disable-application-download-from-the-internet-message-in-mac-os-x/

Saturday, 25 June 2011

New LInux System installed problem

I just installed a new version of Linux (Fedora 15) to take over the works of the old Fedora 14. A problem happened when I was trying to migrate all of the experiment files from the old system's file system. Basically, I have no chance to go through the old system's file system. As far as I remember, at least I was able to access the old system's file system last time after I completed the installation of the new Fedora 15. How comes I failed this time?

After some diggings into the huge Internet, what I found is that the root reason is the duplicated Volume Group names between the old one and the new one. I assumed that I kept the old hard drive installed last time. In this case, the install process change the old system's Volume Group automatically. However, this time I uninstalled all of the hard drive except the new 1T hard drive. The installation has no chance to change them.

 OK, here is the problem analysis. Then, the solution is:

Firstly, I need to check the old system's Volume Group's UID. This is able to complete by checking the directory: /dev/disk/by-id. The currently using Volume Group's ID will be presented there:

ls -l /dev/disk/by-id

Then type the command "lvdisplay ", a WARNING message will be given. The first one UID is the currently using Volume Group's. The later one should be the old system's Volume Group's UID:

lvdisplay /dev/VolumeGroup

After the old system's Volume Group's UID is obtained, using the "vgrename" command to change its name.

vgrename

After this process, all of three Volume Group (two old and one new) are able to be recognized by the new system.

Great!!!

Here is some useful reference: (no promise the availability)

http://linuxers.org/howto/how-mount-linux-lvm-volume-partitions-linux