Desktop Environment (Change)

Change Default Display Manager:

sudo dpkg-reconfigure gdm3 

Check which display manager is running:

systemctl status display-manager.service  or  $ cat /etc/X11/default-display-manager 

Restart GDM:

sudo systemctl restart gdm

Ubuntu + RDP on Oracle Cloud

The first one works the best. Open an SSH connection to the server and run these commands:

sudo su
cd ~
apt update
apt upgrade
apt -y install lxqt sddm xrdp
systemctl status xrdp

The XRDP port needs to be open in Oracle Cloud and search for ‘Virtual Cloud Networks’. Then select the network and go to the ‘Security Lists’ and click on the default one. Then add ingress rules:

The open the port in iptables by editing /etc/iptables/rules.v4

Make a copy of the rule for port 22 and change the value to 3389

Then run:

iptables-restore < /etc/iptables/rules.v4

Create a file in your home folder (/root) called .xsession

nano .xsession

Alternative videos – they may install a different desktop:

Prometheus monitoring stack on Ubuntu 22.04.2 and Micro Kubernetes Cluster (microk8s)

1) Install Ubuntu 22.04.2 desktop

Install guest agent:

sudo apt-get install qemu-guest-agent
sudo systemctl start qemu-guest-agent

Optional – Add the curret user to the sudo group:

sudo usermod -aG sudo $USER

2) Configure RDP and VNC

fix the lock problem:

3) Install docker

sudo apt install

add the current user to docker group:

sudo usermod -aG docker $USER

4) Check docker version

docker --version

5) Create a Micro Kubernetes Cluster (microk8s)

See here:

sudo snap install microk8s --classic --channel=1.27

MicroK8s creates a group to enable seamless usage of commands which require admin privilege. To add your current user to the group and gain access to the .kube caching directory, run the following two commands:

sudo usermod -a -G microk8s $USER
sudo chown -f -R $USER ~/.kube

See the node:

microk8s kubectl get nodes

See the running services:

microk8s kubectl get services

Create an alias:

alias kubectl='microk8s kubectl'

Deploy an app:

microk8s kubectl create deployment nginx --image=nginx
microk8s kubectl get pods

Starting and Stopping MicroK8s:

microk8s stop
microk8s start

export the cluster configuration

kubectl config view --raw > ~/.kube/config

6) Alternatively – install minikube

curl -LO
sudo dpkg -i minikube_latest_amd64.deb

start your cluster:

minikube start

Install kubectl:

snap install kubectl --classic
kubectl version --client

7) Install helm

$ curl -fsSL -o
$ chmod 700
$ ./

or using snap:

sudo snap install helm --classic

8) Deploy Prometheus monitoring stack to Kubernetes with a single Helm Chart


helm repo add prometheus-community

helm repo update

kubectl create ns prom

helm search repo prometheus-community

helm install prometheus prometheus-community/kube-prometheus-stack -n prom

helm install ksm prometheus-community/kube-state-metrics -n prom # install the kube-state-metrics

kubectl --namespace prom get pods

Check configmaps and secrets:

kubectl --namespace prom get configmap
kubectl --namespace prom get secret

Look inside a secret file:

kubectl --namespace prom get secret

Check CRDs

kubectl get crd

9) Access Prometheus Dashboard

$ kubectl port-forward -n prom service/prometheus-kube-prometheus-prometheus 9090

10) Access Grafana Dashboard

$ kubectl port-forward -n prom deployment/prometheus-grafana 3000

default user/password is admin/prom-operator

11) Uninstall Prometheus stack

$ helm uninstall ksm -n prom
$ helm uninstall prom -n prom

12) Install and use K8S Lens to explore what was deployed in the kluster:

How to use the Oracle Cloud free offer and create an Ubuntu Cloud VPS PC on Oracle Cloud using xRDP

Guacamole cannot connect via SSH – FIX

If you get “SSH handshake failed” when trying to use Guacamole to connect to Ubuntu via SSH, you need to use a workaround:

In the meantime a workaround is adding “HostKeyAlgorithms +ssh-rsa” to the end of /etc/ssh/sshd_config on the Ubuntu machine and restart sshd. Note: I don’t have an understanding of the security implications of this, so use at your own risk

The solution was posted here:

Ubuntu 20.04/18.04/16.04 Multi User Remote Desktop Server