Re: Cisco NAT
Notes regarding NAT; Network Address Translation The goal of NAT is to obfuscate addresses. Either source or destination addresses, and either inward or outward bound traffic. In order for NAT to work, it needs to be told several things. ============== 1 What source address(s) to use 2 What destination address(s) to use 3 What interface is considered the inside of a gateway 4 What interface is considered to be the outside of a gateway 5 Which of these ‘sides’ to obfuscate ============== Some of these items can inferred, while some must be explicitly provided. Take for instance a typical situation: One external IP address provided from the ISP with many…
A CISCO Lab
Merry Christmas to those celebrating it. Hanuka for those celebrating that. Kwanzaa for others, and a number of other year-end/year-beginning festivals as well. I wish all of you peace, and good health for yourselves and your families. In another week or two I will be taking the CCNA as one of the final parts of my Bachelor’s degree, so I’m doing a lot of labs. In packet-tracer(from Cisco) and on the Cisco equipment I bought in pursuit of a career in network engineering/operations and security. As part of that process I’ve consumed a lot of content from many sources. From my WGU (my college), from LinkdIn Learning, Pluralsight, Udemy. from…
There’s a Gnome in the KDE
I’m refreshing a laptop that I’m giving to a family member and I want to image the shiny new Ubuntu 20.04 onto a USB3 thumbdrive to send with the machine as a secondary backup to the Ubuntu Linux already installed as primary boot on the laptop as primary backup to Windows10home. For myself, I just use dd from the command line. I’ve found that bit of magic that does notification as dd does it’s thing so you have an idea of it’s progress, so it’s just too convenient these days. But occasionally I’ve wanted to show other people how to ‘burn’ onto a thumbdrive, or onto an SD card for…
Brain dropping: NMAP
I’m starting a ‘brain droppings’ thread. As I do searches for one thing or another I will try to place the actionable results here. For me mainly because if I looked it up once, I will likely be needing it eventually again…and as a public service of sorts in case someone else is looking this stuff up. NMAP on Ubuntu 20.04 The nmap utility is present on Ubuntu 20.04 just as you would expect. However, zenmap is not present. There are ways to get it, such as downloading the .RPM from nmap.org and using alien to convert it into a .deb for installing with dpkg. There is another GUI for…
Installing nextcloud on a Digitalocean droplet: notes
As an exercise to utilize some of the functionality I am
Notes in the Aether
I had a need to change the boot order in GRUB to hide the fact that Linux is present on a laptop I am giving to a relative. When Windows borks, not if, I want to be able to help her rescue her machine over the phone or possibly even remotely. So while I’m refreshing myself on the wonders of GRUB2, I thought I’d make some notes to collect a good explanation of GRUB here while I’m at it. When adding groups or such to your account, instead of ‘logging out and back’ in just initiate a switch-user to your username. Part of moving to a new user is accepting…
An Enigma in a Linux wrapped inside a Windows.
It comes to us from 1983 and was originally shipped as a software bundle-in when you bought Microsoft's newly developed user interface. The $195 Microsoft Mouse!
Some terminal commands that I've had to look up. I figure if I looked it up once, I might need it again.
AAA: Authentication, Authorization, and Accounting
A good way to become accustomed to using the Terminal is to just use it. Ideally for as much of your normal tool-chain as you can. In this article I will document how to use the Linux Terminal to download an Ubuntu OS image from Canonical and then check it’s SHA256 checksum to ensure it is authentic. One thing that we all should do is verify that the images we are pulling from Canonical, Red Hat, Suse, Fedora, etc., are legitimately the images we think they are and not the image a hacker wants us to use? Well, looking for the lock symbol next to the URL at the top…
Gaming on Linux!
Yeah, that’s right. Linux. Gaming. The operating system that rules the interwebs, powers all major supercomputers, light bulbs, and hobby Raspberry Pis, actually plays games! And of course it does it VERY well! So, to be clear most games written currently are written with Windows10 as their main audience. But many are written for Sony’s Playstation, which runs a variant of Linux. Also some are written to target Google Stadia, the online games channel for Google and these are also running Linux, and a very mainstream version of Linux. If you wanted to have all the security and stability features of running Linux. But you want to get your gaming…