Thursday, September 30, 2021

Attempt to test Web Cockpit Console on Fedora 35 Beta Server (VENV)

 First - Fedora 35 Beta Server deployed as L1 KVM Guest on F34 Bare metal Server . Nested virtualization enabled via virsh console on F34 Server. Complete KVM && Cockpit install performed on L1 F35 Server Guest per https://computingforgeeks.com/how-to-install-kvm-on-fedora/

 Second - Debian 11 L2 KVM Guest has been deployed via Web Cockpit Console on F35 Beta Server L1 Guest with no issues.

See http://lxer.com/module/forums/t/36755/

Debian 11 L2 Guest (UEFI mode installation) virtual drive has been intensionally configured with Debian Calamares Installer.











































Connection via ssh from F34 Bare metal Server instance to L2 Debian 11 Guest been deployed utilizing Cockpit Console set up on F35 Server L1 Guest















Obtain `df -Th` on Debian 11 L2 Guest















Display IP address of Debian 11 L2 Guest
















Tuesday, September 21, 2021

Sunday, September 19, 2021

Set up Virtual Box on top of Server F35 (pre release) via rpmfusion (VENV)

 First I've installed the most recent nightly build of Fedora 35 Server on Fedora 34 Bare metal KVM Virthost as Guest OS with "Fedora Workstation" desktop, like virtual machine seating on the Linux bridge been created via Web Cockpit Console. When done issued the following set of commands on F35 Guest

$ sudo dnf install  \

https://download1.rpmfusion.org/free/fedora/rpmfusion-free-release-$(rpm -E %fedora).noarch.rpm 

$ sudo dnf  install \

https://download1.rpmfusion.org/nonfree/fedora/rpmfusion-nonfree-release-$(rpm -E %fedora).noarch.rpm

$ sudo dnf install \

VirtualBox kernel-devel-$(uname -r) akmod-VirtualBox

$ sudo akmods

$ sudo systemctl restart vboxdrv 

$ lsmod  | grep -i vbox

Afterward performed a test install of Debian 11 as Oracle VBOX 6.1.26 virtual machine ( I did this installation in UEFI mode manually partitioning virtual drive with Calamares and nested kvm enabled )











































By the way, all Fedora 34 Bare metal Servers ( KVM VirtHosts ) are currently running under 5.14.5 fedora kernel. One Intel-based i4790, 2xBX500 SSD, another Ryzen 7/3700 based with WD500 NVMe SSD.

https://koji.fedoraproject.org/koji/packageinfo?packageID=8

Quick Enable

$ sudo dnf copr enable jforbes/kernel-stabilization



Wednesday, September 15, 2021

Python (numpy && matplotlib) solving one relatively difficult math problem

The problem itself is to find all solutions of the following equation on real axis

cos (cos (cos (cos (x)))) - sin (sin (sin (sin (x)))) = 0

We intend to prove that equation above doesn't have any solution via creating a python script importing NumPy and Matplotlib. Just recall that the function understudy has a period of 2*pi .

[boris@fedora34server ~]$ cat  yandexPlot5.py

import numpy as np # import numpy package

import matplotlib.pyplot as plt # import matplotlib.pyplot package

x = np.arange(0,9 * np.pi, 0.1) # create x array of angels from range 0 to 9*3.14

y = np.cos(np.cos(np.cos(np.cos(x)))) -  np.sin(np.sin(np.sin(np.sin(x)))) 

plt.plot(x, y) # plot grah 

plt.title(" Graphical Representation of sine function")

plt.xlabel("x axis ")

plt.ylabel("y axis ")

plt.show() # show plotted graph















Thus mentioned equation doesn't have any solution. Moreover increasing number of nested sines and cosines produces similar plotted graphs

































Wednesday, September 8, 2021

Deployment KVM Guests via Cockpit Console on Manjaro KDE 21.1.2

I am posting this Howto due to currently available instructions on the Internet don't focus the user's attention on installation packages "ovmf" and "virt-viewer" on the most recent release Manjaro KDE .  Skipping mentioned packages causes issues with Remote Viewer ( Cockpit Console ) and the ability to deploy KVM guests in UEFI mode

Install KVM and Cockpit Console

$ sudo pacman -S virt-manager qemu vde2 ebtables dnsmasq \
  bridge-utils openbsd-netcat virt-viewer ovmf
$ sudo systemctl enable --now libvirtd.service

$ sudo vi /etc/libvirt/libvirtd.conf
Uncomment
#unix_sock_group = "libvirt"
#unix_sock_ro_perms = "0777"
#unix_sock_ro_perms = "0777"

$ sudo systemctl restart libvirtd.service

Cockpit console setup
$ sudo pacman -S cockpit
$ sudo systemctl enable --now cockpit.socket

Tuning firewall
$ sudo apt install firewalld
$ sudo systemctl enable --now firewalld
$ sudo firewall-cmd --add-service=cockpit --permanent
$ sudo firewall-cmd --reload