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 https://github.com/brektrou/rtl8821CU.git

Step 2: Build and install

cd ~/build/rtl8821CU
make
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/domain_name.lt.san_config
rm -rf /usr/local/directadmin/data/users/user_name/domains/domain_name.lt.cert.creation_time

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

#!/bin/bash
VMWARE_VERSION=workstation-15.0.4
TMP_FOLDER=/tmp/patch-vmware
rm -fdr $TMP_FOLDER
mkdir -p $TMP_FOLDER
cd $TMP_FOLDER
git clone https://github.com/mkubecek/vmware-host-modules.git
cd $TMP_FOLDER/vmware-host-modules
git checkout $VMWARE_VERSION
git fetch
make
sudo make install
sudo rm /usr/lib/vmware/lib/libz.so.1/libz.so.1
sudo ln -s /lib/x86_64-linux-gnu/libz.so.1 
/usr/lib/vmware/lib/libz.so.1/libz.so.1
sudo /etc/init.d/vmware restart

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

Upgrade Ubuntu 16.04/17.10 to Ubuntu 18.04 From Command Line

You can use command line to upgrade Ubuntu desktop or a headless server. Speaking of servers, it is recommended that you upgrade Ubuntu on a test server before doing it on a production server.

If you use SSH to log into your Ubuntu server, it’s a good idea to keep your OpenSSH session alive by adding the following line in /etc/ssh/sshd_config file on your server.

nano /etc/ssh/sshd_config
ClientAliveInterval 60

Save and close the file. Then restart SSH daemon.

systemctl restart ssh

To upgrade to Ubuntu 18.04, first run the following command to upgrade existing software.

apt update && apt dist-upgrade

Then make sure you have update-manager-core package installed.

 apt install update-manager-core

After that, run the following command to begin the upgrade process.

do-release-upgrade

Then follow the on-screen instruction to upgrade to Ubuntu 18.04. Once the upgrade is finished, reboot your Ubuntu desktop or server. To check your Ubuntu version, run:

lsb_release -a

Output:

No LSB modules are available.
Distributor ID:	Ubuntu
Description:	Ubuntu 18.04 LTS
Release:	18.04
Codename:	bionic

You also need to re-enable third-party repositories such as PPA because they are disabled during upgrade.

Attention: this update will not work on dedikuoti.lt OpenVZ servers except KVM servers.

OpenVZ container will return this message:

This version of the GNU libc requires kernel version 3.2 or later. Please upgrade your kernel before installing glibc.

 

How To Install Apache Tomcat 9 on Ubuntu 16.04

Apache Tomcat is a web server and servlet container that is used to serve Java applications. Tomcat is an open source implementation of the Java Servlet and JavaServer Pages technologies, released by the Apache Software Foundation. This tutorial covers the basic installation and some configuration of the latest release of Tomcat 9 on your Ubuntu 16.04 server.

Continue reading “How To Install Apache Tomcat 9 on Ubuntu 16.04”

How to solve the “changed its ‘Origin’ value from ‘Google, Inc.’ to ‘Google LLC'” APT error

If you are on Debian or Ubuntu and using Google official repositories for Google Chrome Remote Desktop, you might have received the following error while updating your system.

E: Repository 'http://dl.google.com/linux/chrome/deb stable Release' changed its 'Origin' value from 'Google, Inc.' to 'Google LLC'
N: This must be accepted explicitly before updates for this repository can be applied. See apt-secure(8) manpage for details.

Just run

sudo apt update

And you will be prompted to accept the new Origin of the repository

Do you want to accept these changes and continue updating from this repository? [y/N] 

And that’s it.