In our last post we examined the possibility to recover deleted data from USB keys and disks. Today we want to focus your attention on the proper way to destroy sensitive data from your disks.
On Ubuntu you have the possibility to move any file to the Trash but, as we demonstrate in our last post, anyone has the possibility to recover them using a simple, basic GUI, program called PhotoRec.
If you want to be reasonably sure that none will be able to recover a file you decided to permanently delete you have to use the Shred command. Shred is native in Ubuntu Kernel and literally delete your files overwriting them repeatedly with arbitrary data. After you delete a file with Shred you can be sufficiently sure that recovering procedures will not succeed.
As usual we must warn you that technology is rapidly evolving and what could be considered sure today, tomorrow will be out of date! So, if you think you need to preserve your privacy in the best way, don’t forget to change the hard disks regularly and mechanically destroy your old ones. Sincerely we hope our readers haven’t this kind of need.
To start using Shred on Ubuntu you have to open a Terminal and type:
sudo shred –help
In this way you will visualize the grammar and all the possible options offered by this program.
The correct grammar to use Shred is:
shred [OPTIONS] FILE
or, if you want to shred a entire partition:
shred [OPTIONS] /dev/[HDA9]
The possible options are:
-f, –force change permissions to allow writing if necessary
-n, –iterations=N overwrite N times instead of the default (3)
–random-source=FILE get random bytes from FILE
-s, –size=N shred this many bytes (suffixes like K, M, G accepted)
-u, –remove truncate and remove file after overwriting
-v, –verbose show progress
-x, –exact do not round file sizes up to the next full block;
this is the default for non-regular files
-z, –zero add a final overwrite with zeros to hide shredding
–help display this help and exit
–version output version information and exit
In our experience, to operate in the fastest way, we decided to add Shred on the Nautilus Menu and have the command ready with a simple right click on the mouse.
For this reason you have to open a Terminal and type:
sudo apt-get install nautilus-actions
Then you launch the program following this path: System->Preference->Nautilus Actions Configuration.
Last, you have to configure Shred filling e.g. the following parameters:
Label: Shred
Tooltip: Shred utility to securely erase files
Icon: gtk-dialog-warning
Path: shred
Parameters: -f -u -v -z %M
Filenames: *
Mimetypes: */*
Appears if selection contains: Both
Be sure to check the box “Appears if selection has multiple files or folders“
To finish your configuration, do not forget to open again a Terminal and type:
nautilus -q
nautilus
If you use Ubuntu 10.04 or any other Linux distribution which doesn’t automatically upgrade your Firefox to the latest version you can force it.
First of all you have to launch Terminal and add the right PPA to the repository:
sudo add-apt-repository ppa:ubuntu-mozilla-security/ppa
Then you need to update and upgrade the OS using:
sudo apt-get update sudo apt-get upgrade
If you are installing Firefox for the first time the right commands are:
sudo add-apt-repository ppa:ubuntu-mozilla-security/ppa sudo apt-get updatesudo apt-get install firefox firefox-gnome-support firefox-locale-en
As usual on Linux, it is not necessary to reboot the computer and you can start immediately to use your updated Firefox.
After I installed some new software I wasn’t able to update Ubuntu 10.04 LTS. The Update Manager was not able to check for updates and when I tried to use the Synaptic Package Manager I hadn’t better results. A reboot was not the right solution and I tested different ways to solve my problem saving the Ubuntu installation in my computer.
Searching on internet I discovered that there are few possible solution to avoid this problem and, in case you have the same bug on your computer, I decided to sum-up the most powerful after I successfully tried them.
First of all you can try to force the update process through the Terminal typing:
sudo apt-get update sudo apt-get upgrade
If this doesn’t work you will try with this next step:
sudo rm var/lib/dpkg/lock sudo dpkg --configure -a
Then launch again the Update Manager to verify if you succeed and if nothing happened solve the matter typing:
sudo rm /var/lib/apt/lists/* -vf sudo apt-get update
and try again to launch the Update Manager.
In my case this was enough to restore all the Update Manager features and solve the problem. If you have extra problems about this bug or if you want to suggest alternative solutions, please, don’t hesitate to comment this post.
Christmas time is ending and today we really don’t know how many relatives used out computer for “just few minutes” or “to quickly (sic) check the emails”. In few words, our Linux PC could have been overstuffed with unwanted temporary files and we haven’t had time to update it. So, it’s time to clean-up!!
First of all I suggest to use BleachBit because, for my experience, it’s the most powerful software to clean temporary files, log files and unwanted traces on your computer. BleachBit is easy to use and, as we described in previous post, very effective.
Then we have to check if our system is really updated so we can use the usual ways as Synaptics Package Manager or quickly run a some simple commands through Terminal to update, upgrade and remove old packages or Kernel.
For this purpose I collected three simple commands and chained them in a single line:
sudo apt-get update && sudo apt-get upgrade && sudo apt-get autoremove
In this way you will be sure that you can start again to work on your Ubuntu as before the Christmas time!
The last generation of external 3.0 usb disks allows us to create fast multi-boot drive that can be used for different purpose. Commonly we use these “special” drives as recovery tools when something goes wrong in our computers or when we would dig, in a deeper way, a particular desktop.
The best software to create multi-boot disks or ISO have been developed for Windows and the only exception is a French, multi-step solution named LiveUSB Multi-Boot.
Today we focus our attention on Sardu a multi-language Italian project developed for Windows machines. After you have downloaded it you can unzip and save the folder in your favorite location. The sardu.exe file will run the program and you can start to decide if you prefer to create a multi-boot ISO or a multi-boot usb key.
The menus are complex but in a couple of minutes you will be able to properly navigate them and select the software and ISO you’d like to have in your CD or USB key. You can also decide to manually add a specific ISO which is not directly supported.
The CD-DVD burner is included in Sardu consequently you can create your bootable CD-DVD in just few clicks.
In the everyday world, Sardu is also useful to test computers when you want to quickly install a Linux distribution and you are not sure about the best one to choice.
Moreover, Sardu is plenty of extra freeware which can help you to recover the GRUB, partitions, lost files and passwords.
Unfortunately Wine is not able to run Sardu in a correct way and when we tested it on Ubuntu we were able to use just few basic features.
Computer Borders 