Securely eraseing disk and file

 I used Hiren's Boot Disc and DBAN boot disc to erase my HDD securely most of the time.  I did use dd command but found out there were few other useful commands recommended in this link.  

The first one mentioned in the article is quite useful.  It will overwrite the disk five times and add a final overwrite with zero to hide shredding.

 # shred -n 5 -vz /dev/hda

The command below will use shred and /dev/urandom as the source of random data.

 


shred -v --random-source=/dev/urandom -n1 /dev/sda

 

Another option is to install scrubbing program like scrub in Unix.  You can use it to erase a single file with algorithm.  

scrub -p nnsa|dod|bsi|old|fastold|gutmann|random|random2 fileNameHere

 

Or you can even use it to erase disk with dod standard.  

scrub -p dod /dev/sda

 

*** WARNING: Please test the commands before running it on your data.  Commands mentioned in this article will delete the data permanently.  *** 


  

Installing VMware Workstation Pro in OpenSuSE LEAP 15.4

Now system is up and running fine.  Next is to install VMware Workstation Pro.  Basically, it is my OpenSUSE LEAP 15.4 is my host. 

Make sure system is up to date and install the required packages.  Download the binary and copy it to a tmp folder.  Then add the execute permission to the bundle. 

sudo zypper update
sudo zypper install kernel-source kernel-devel gcc

Download the binary and copy it to a tmp folder.  Then add the execute permission to the bundle.   Run the installation after. 

sudo chmod +x VMware-Workstation-Full-16.2.4-20089737.x86_64.bundle
sudo ./VMware-Workstation-Full-16.2.4-20089737.x86_64.bundle

Reboot.  Then I receive the errors below one by one.  

 

  

Do some researches and follow instructions in this video.  

First get the VMware version
vmware -v

Then, download the patches needed to build the VMware host modules against the recent kernel.  You may need to rebuild it if VMware does not start after update.   See https://github.com/mkubecek/vmware-host-modules

wget https://github.com/mkubecek/vmware-host-modules/archive/workstation-16.2.4.tar.gz

tar -xvzf workstation-16.2.4.tar.gz
cd vmware-host-modules-workstation-16.2.4/
tar -cf vmmon.tar vmmon-only
tar -cf vmnet.tar vmnet-only
sudo cp -v vmmon.tar vmnet.tar /usr/lib/vmware/modules/source
sudo vmware-modconfig --console --install-all

I setup a script to start vmware every time the host boots up.  

/etc/init.d/vmware start

I found out none of the USB devices list under Removable devices of the VM.  So, I suspect the vmware-usbarbitrator is not started up auto.  Add the following line to the start up script.  Now, I can see the USB device.

/usr/bin/vmware-usbarbitrator start 

One issue I found and other ppl complain in other Linux distro too.  If you try to copy from VM and paste on the Linux host, you will get error below.

There seems to be no solution to it.  However, if you check your /home/user/.cache/vmware/drag_and_drop/ directory, you will actually find the file there.  

OpenSUSE LEAP 15.4 as physical host

There are still some issue with USB3 for Debian / Ubuntu on my old Gigabyte GA970A-D3P.  I decide to rebuild that with OpenSUSE LEAP 15.4.  I don't need a lot of power.  So, AMD CPU FX8320 I got back in 2013 is good enough.  I follow the link below.  It is self-explanatory.  

https://doc.opensuse.org/documentation/leap/startup/html/book-startup/art-opensuse-installquick.html

For NIC, I just set it up for IPv4.  Enable firewall and disable ssh.  Keep SecureBoot to test Windows 11 as VM in the future.  I don't like the GNOME desktop and it looks like a table to me.  So, I select Xfce instead.  Since it is a physical host, I remove tools I don't need like SAMBA (if need to share files, I will use USB drives instead), Thunderbird, Transmission and Pidgin.  So, I remove them. 

Installation runs fine.  nouveau is used for the NVIDIA GT630 and Realtek 8812BU WiFi adapter is not working.  

So, I decide to use NVIDIA driver instead of nouveau driver.  After installing G05 driver, the resolution drops to 640 x 480.  Exactly as what's described in this post below.

https://forums.opensuse.org/t/leap-15-2-nvidia-driver-does-not-work/141453

I decide to go with G04, and everything works as expected.  I don't follow the instructions found in https://en.opensuse.org/SDB:NVIDIA_drivers. 

Instead, I go to https://opensuse-guide.org/3d.php and install the GeForce 400 series drivers.  The 1 click option will add NVIDIA repository.  Once installation completed, reboot and open NVIDIA X server settings to confirm installation is successful.
 

 

 

 

 

 

For 8812bu adapter, since mine is USB, I run lsusb to confirm the model number. 

Then, follow instructions in https://github.com/morrownr/88x2bu-20210702  If driver fails after system update, please follow instructions in the link to fix it.   I copy the steps from the link. 

1) confirm system is up-to-date by running

sudo zypper update

Then, reboot after update completes.

2) Install required packages

sudo zypper install -t pattern devel_kernel dkms

3) Create a directory to hold the downloaded drivers and move to the newly created directory

mkdir -p ~/src

cd ~/src

4) Download the driver

git clone https://github.com/morrownr/88x2bu-20210702.git

 

5) Move to the newly created driver directory

cd ~/src/88x2bu-20210702

 

6) Run the installation script but it complains about missing iw package.  So, install iw package first then run the script.  

 

 

 

sudo zypper install iw

sudo ./install-driver.sh

7) Reboot

There is a warning about kernel update.  If you decide to upgrade to a new version of kernel such as 5.15 to 5.19, you need to remove the driver you have installed and install the newest available before installing the new kernel. Use the following commands in the driver directory:

$ sudo ./remove-driver.sh
$ git pull
$ sudo ./install-driver.sh

For the 8812BU WiFI, I see another similar link https://www.fastoe.com/blog/install-rtl8812bu-usb-wifi-dongle-on-linux with driver build and installation steps. 

smartmon tool is installed during the SUSE installation.  So, I just need to run the smartctl -a /dev/sdX to look for any disk errors.  Or install gsmartcontrol if you want a GUI.

I have an USB drive to store my documents and pictures.  On the safe side, I have a 2nd USB drive as a backup of backup.  To sync them up, Grsync is used.  

When I open the yast2 firewall, I do not see the wireless adapter listed.  So, I wonder if it is protected by firewall.  Going thru the documentation, firewalld replaced SuSEfirewall2 in SUSE 15.  I run the command below to confirm the wireless adapter is assigned to the public zone.  

firewall-cmd --get-zone-of-interface=wlan0