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Create encrypted FS in a file #Create a file and allocate its size : here 1GB dd if=/dev/zero of=encrypteddrive bs=1024 count=1048576 #Setup the encrypted file cryptsetup -y luksFormat encrypteddrive (enter passphrase and confirm) #Open the Encrypted device sudo cryptsetup luksOpen encrypteddrive secretdata  (enter password)    #Create an EXT4 filesystem inside the encrypted file sudo mkfs.ext4 /dev/mapper/secretdata #Create a directory to be the mountpoint mkdir ../mp-encrypted #Mount the encrypted FS  sudo mount /dev/mapper/secretdata ../mp-encrypted/ #After use, unmount the encrypted FS and close the encrypted file sudo umount  ../mp-encrypted/ sudo cryptsetup luksClose secretdata Use: #To access Data, open the file and mount it sudo cryptsetup luksOpen encrypteddrive secretdata sudo mount /dev/mapper/secretdata ../mp-encrypted/ #To close after use, unmount the partition and close the file sudo umount  ../mp-encrypted/ sudo cryptsetup luksClose secretdat...

 For a basic usage of GNS3, some configuration is needed after you install "gns3" and "gns3-server" in your Manjaro or Arch Linux machine. Required group permissions for the linux user are "wireshark" (for using the live capture of packets) and "libvirt" (for using virtualization capabilities, required for example for NAT, as mentioned in the previous blog entry). Commands to execute are : sudo usermod -aG wireshark user sudo usermod -aG libvirt user replace "user" with your username for the Linux session. 

Problem: You can't add a NAT connection to your GNS3 simulation, and you get the error : "ERROR template_manager:226 Error while creating node from template: NAT interface virbr0 is missing, please install libvirt" Steps to resolve: 1- Create a file named /tmp/default.xml 2- Paste this content and save: <network>   <name>default</name>   <bridge name="virbr0"/>   <forward mode="nat"/>   <ip address="192.168.123.1" netmask="255.255.255.0">     <dhcp>       <range start="192.168.123.2" end="192.168.123.254"/>     </dhcp>   </ip> </network> 3- Execute the following commands in your shell : virsh net-define /tmp/default.xml sudo virsh net-start default sudo virsh net-autostart default  

 Based on this VyOS knowledge base article  , restarting the routing daemons, like OSPF, would be as easy as typing "restart ospf". But while working on a VyOS 1.3 appliance in GNS3, I couldn't simply do that : it turns out that VyOS now uses FRRouting, and this implies a new command syntax. The correct command to restart ospfd for example is now : "restart frr ospf". The same thing applies for other routing protocols.

Imagine Debian was a rolling release Microsoft doesn't spy on you Imagine Youtube with no ads facebook and twitter too Imagine Apple was cheaper And Sun Microsystems still here Imagine C with no pointers it's easy if you do Imagine there is no secure boot bloatware not on ubuntu Imagine all the systems being free and opensource ! You may say I'm a dreamer But I'm not the only one I hope someday you'll join us And the internet will be as one

( Cet article a été publié originalement dans le magazine de la 7ème édition du Forum DSI International )   L’informatique joue un rôle central dans le monde d’aujourd’hui, et ça va continuer tant que la technologie progresse : la sécurité informatique sera par conséquent un des enjeux principaux de l’humanité.  Le virus, un objet minuscule et inaperçu, a une très grande ressemblance avec les programmes informatiques. Cet agent qui infecte son hôte, généralement une cellule vivante, et se réplique, n’est même pas considéré comme un être vivant. Toutefois, en injectant ses éléments génétiques dans le génome de son hôte, il arrive à se reproduire et envahir plus de cellules, voire des organes entiers.  Le mode opératoire d’un virus informatique n’est pas vraiment très différent. Historiquement, le premier virus informatique, nommé « Creeper », a été développé pour des fins pédagogiques. Il a fallu attendre 15 années pour l’apparition d’un virus informatique en dehors de l’e...

 A man arrives at a hotel after a long train journey, exhausted. He comes into a communal room and sees three other guys who are drunk and talking loudly. They are cracking anti-government jokes and laughing at Khrushchev. The man is annoyed that he can’t sleep so he hatches a plan. He walks out into a corridor and asks a staff member to bring him a cup of tea. He then comes back into the room and starts talking to the noisy fellows:  “Comrades, you shouldn’t joke like that here. Every room is bugged, you know...”  “Nonsense! Who would listen to us?”  “Well, let me show you”  The man walks up to a socket and says into it:  “Comrade major, can I have a cup of tea please?”  Sure enough, the staff member soon enters with a cup of tea.  “See, told you.”  The three men are pale and quiet for the entire night, so the tired man finally gets some good sleep.  He wakes up the next morning alone. He walks downstairs and asks the receptionist about...