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Setup 2FA on centos 8/fedora/rhel based distros
Important note!! If you are facing issues with logging in, check if selinux is running and either disable it or change the contexts. selinux blocks reading your google-authenticator key files. trial and error dnf…
Docker day 1
This article is a work in progress. Email your suggestions to kevin@fivemin.net. Build, swap and remove infrastructure in a text file Docker containers are a set of tools to quickly and easily build, swap out and remove…
What is the difference between tagged and untagged vlan ports? Tagged = trunk ports, untagged = access ports
VLAN-enabled ports are generally categorized in one of two ways, tagged or untagged. These may also be referred to as “trunk” or “access” respectively. The purpose of a tagged or “trunked” port is to pass traffic for…
List of networking management software
# software Age Link Comment 1 SNMP-C 23/01/1990 https://www.castlerock.com/products/snmpc/ # software Age Link Comment
What are NNI and UNI ports on access switches?
These distinctions are common in metro area networking were an ISP needs to keep track of their uplink and downlink ports. NNI ports = Network Interface Port = Uplink port = WAN ports. NNI port characteristics include…
why is the command line interface needed cant we just write configurations by hand?
Sure! If you know the configuration language its easy to write a configuration file. Command line interfaces are often used to format your configuration file in a very specific manner, one can think of the CLI as an…
What is the difference between console ports and management ports on switches?
Console ports enable console connections using, usually, a USB to db9 connector. These ports are usually used when first setting up a switch were the technician has physical access to the switch. Management ports are…
virt-manager is deprecated and moving to the cockpit project, RHEL/CENTOS/FEDORA
Different alternatives exists to manage kvm guests: * Cockpit Webgui - Limited functionality, works in any webbrowser after enabling webgui and the webgui virtualization plugin on the server * Virt-manager GUI -…
qemu/kvm/libvirt guests, up and running checklist
Updated continually, Getting started with libvirt, a checklist Requirements: KVM hypervisor/virtualization packages on your virtualization host/libvirt host Management can either be done using: * Command line, the virsh…
SPICE server slow performance, change display server from wayland to xorg
This post is a part of “up and running with libvirt guests series” myLibvirtGuest# echo $XDG_SESSION_TYPE #check current display server wayland myLibvirtGuest# logout At the login screen, select the "gear" icon and…
Enable copy paste in libvirt guests, Install spice-vdagent using libvirt centos 8
This post is a part of “up and running with libvirt guests series” Tldr: see below instructions for centos 8 myLibvirtHost# virsh destroy myguest myLibvirtHost# virsh edit --domain myguest # ADD BELOW CODE SNIPPET…
What is localhost, 127.0.0.1 and loopback-address ? Hint: Different ways to reference your computer
tldr: the dns name Localhost or ip address 127.0.0.1 is a reserved network address that always mean YOUR OWN COMPUTER/HOST/NODE, these addreses are assigned to the loopback interface. Localhost or 127.0.0.1 are by…
vlc transparent
To make the playback window always on top select Video -> Always On Top from the menu. (Mac Video -> “Float on Top”) I don’t see a way to change the transparency when VLC goes out of focus without using a window manager…
KVM vs ILO/IDRAC/IPMI for out of band management
tldr: ILO is integrated and requires more configuration, KVM can be installed a top of rack switch but not give power on/off functionality like KVM more here soon
"Open message in conversation" does not work or do anything Thunderbird solution
This can be because the message gets marked as 'hot', when unchecking 'hot' from the message it can be read in the 'open conversation' view again. Go to the 'send' inbox and search for the conversation using the info in…
What is "Cut-through", "store and forward" and "fragment free" switching methods?
Switching methods forward layer 2 frames in different ways * Cut through * Store and forward * Fragment free Cut-through switching reads only the the destination part of mac header which means that the switch will begin…
What is a nonblocking switch fabric / architecture?
Switchports are tied to a back-plane or “fabric”, the back-plane coordinates switching between ports and end devices. Sometimes there is a discrepancy between the processing power of the back-plane and its switchports:…
Cant connect to hyper v manager, probably because you don't have permissions for your current user
Solution: COMPUTER MANAGEMENT > Local Users and groups > groups > hyper v > add user to hyper v group > sign in and out
The Virtual Machine Management Service encountered and error while configuring the hard disk
TLDR: you already have a hard disk created in your save folder with this name. Remove it or rename your vm.