How to login SSH with .ppk file on Ubuntu terminal

You can convert a .ppk file in Ubuntu with installing putty-tools. So

sudo apt-get install putty-tools

Then youn can convert the .ppk file with puttygen to OpenSSH’s format like so:

puttygen <the_key.ppk> -O private-openssh -o <new_openssh_key>.key

How to install Samsung SCX-4623FW unified printer driver on Ubuntu 19.04

Step 1: Download Samsung SCX-4623FW linux driver

Samsung SCX-4623FW Linux Driver Details
Size: 14.66 MB, GZ
Version : V1.00.36_00.91


Run command:

cd /tmp

Step 2: Extract archive

Run command:

tar xzfv uld_v1.00.36_00.91.tar.gz

Step 3: Install drivers

Run command:

cd uld/
sudo sh ./

For network Samsung scanners, put your scanner’s IP address and optionally port anywhere in the file /etc/sane.d/xerox_mfp.conf:

tcp host_address [port] 

Step 4: Reboot your computer

Run command:


How to install Realtek 8811CU Wireless LAN 802.11ac USB NIC on Ubuntu 19.04

Before build this driver make sure make, gcc, linux-header and git have been installed.

Step 1: Clone brektrou repository

mkdir -p ~/build
cd ~/build
git clone

Step 2: Build and install

cd ~/build/rtl8821CU
sudo make install

Step 3: Check installed driver

If you successfully install the driver, the driver is installed on /lib/modules//kernel/drivers/net/wireless/realtek/rtl8821cu. Check the driver with the ls command:

ls /lib/modules/$(uname -r)/kernel/drivers/net/wireless/realtek/rtl8821cu

Make sure 8821cu.ko file present on that directory.

How to disable Let’s Encrypt for the hostname

If you want to replace the certificate for your hostname with a custom certificate but you had enabled Let’s Encrypt, you will need to disable Let’s Encrypt for the hostname first. The following command let’s DirectAdmin know that it does not need to renew the Let’s Encrypt certificate. This is required as DirectAdmin will renew the certificate +/- 60 days after the last renewal, even when the Let’s Encrypt certificate is not installed.

rm -rf /usr/local/directadmin/data/users/user_name/domains/
rm -rf /usr/local/directadmin/data/users/user_name/domains/

How to set up software RAID1 on a running LVM system (incl. GRUB2 configuration) (Ubuntu 19.04)

This guide explains how to set up software RAID1 on an already running LVM system (Ubuntu 19.04). The GRUB2 bootloader will be configured in such a way that the system will still be able to boot if one of the hard drives fails (no matter which one).

I do not issue any guarantee that this will work for you!

Continue reading “How to set up software RAID1 on a running LVM system (incl. GRUB2 configuration) (Ubuntu 19.04)”

Installing VMware on 19.04: Failed to build vmmon

I found a solution on mkucebek’s github sources

rm -fdr $TMP_FOLDER
mkdir -p $TMP_FOLDER
git clone
cd $TMP_FOLDER/vmware-host-modules
git checkout $VMWARE_VERSION
git fetch
sudo make install
sudo rm /usr/lib/vmware/lib/
sudo ln -s /lib/x86_64-linux-gnu/ 
sudo /etc/init.d/vmware restart

Then, you just have to launch VMware Workstation without building modules.