Archive for the ‘Computer’ Category

Finally finally done…

Friday, October 25th, 2019
block puzzle screenshot

In case you don’t know, this is the app called Block Puzzle (on Android). After 7 years of puzzling, I managed to finally solve the last remaining puzzle (#491) on 24. 10. 2019 at around 14:49 – in an airplane flying from Dublin to Paris. Perhaps as decadent as it gets.

I already asked the person who introduced me to Block Puzzles not to show me any more puzzles, thank you very much.

Anyway, done and happy with it.

The series continues…. CompTIA CASP+

Friday, October 11th, 2019

I started work extra early, left early and gave it all.

It was worth it: I passed the CompTIA CASP+ (003) exam today. First try, like all the other IT exams so far.

Again, CompTIA exam. Vague on purpose so I felt terrible during the exam. Out of 80 questions I had almost half marked for review but after two out of three hours and two review rounds I handed the exam in… et foilĂ .

This particular exam does not give you a score, just a pass / fail result.

The beloved (dreaded) Red Hat 5 server simulation was there as well as the download simulation.

The range of difficulty of the questions is so wide…. some questions are really simple (or at least seem to be as I don’t know if I got them right or not), other questions… no clue at all about the correct answer.

Tonight it’s time to celebrate… next week Thursday I’ll take on the CKAD exam, the last one for this year. Keep your fingers crossed for me.

minikube, macOS and virtualbox

Friday, October 11th, 2019

minikube is an awesome tool to play around with Kubernetes and it’s easy to install on macOS if you already have brew installed (not much harder if you just follow the instructions on kubernetes.io though)

But sometimes, just sometimes…. spinning up a Kubernetes cluster with minikube does not work… it gets stuck somewhere. You can crank up the debug level which will fill your screen your message and you can searchengine whatever error message it spits out and try to fix it. I’ve tried it but it takes and usually does not bear frut. In the end doing the following always fixed the issues:

shutdown any minikube clusters that are running (on purpose or not)
make sure virtualbox is turned off (when in doubt, check with ps aux | grep -i virtualb )
rm -rf .minikube
rm -rf .kube
brew cask reinstall virtualbox
if you’re feeling adventerous, you can upgrade minikube and kubectl at the same time.
then spin up minikube again: minikube start -p <yourclusternamehere> (I like not using the default cluster)

An awesome series continues…. CISSP exam passed

Friday, September 13th, 2019

On 20190912, I took and passed the CISSP exam after several months of preparation. Yay for me!

What about that series I mentioned? It’s becoming scary but I haven’t failed any IT exam / certification so far… MCP, LPIC, federal tests, CompTIA and now the CISSP exam. Of course I’m glad about this, but it’s getting spooky.

What was the test experience like? The checks until the actual exam starts is the most annoying part… identification, NDA, vene scan, everything twice. To some degree I can understand that, but the vene scan in top of passport checks? Hm…

One thing on the actual exam I was quite worried about is that you cannot go back to previous questions… click Next, no way to go back. So many times I did not feel particularly confident about the selected reply… but you can’t go back, so worrying about it is useless.

The other thing I was not prepared for was the questions that asked for best something / most appropriate something… practice questions were more fact-based and if anything they asked “what is the first thing to do when…” or “the last thing to do when…” – which is a different dimension from “what is the best thing to do when…” as that implies the listed possibilites could all be correct but one is ‘more’ correct and the deciding factor is not necessarily a technical factor.

Anyway, I felt quite burned out after 80 questions and was hoping that I would not have go higher than a 100 questions. Which is exactly what happened… the result is not even shown on the screen, only on the printout. I did not feel confident regarding the result so imagine my surprise.

Here’s what I used for preparation:
Linux Academy CISSP preparation course
Official CISSP Guide 3rd edition 2016
Some lectures on pluralsight.com and many practice questions on kaplan.com (linked to pluralsight)
Some lectures provided by thorteaches.com
An app called CISSP Professional with practice questions

Find your wifi adapter mac address without ifconfig

Tuesday, June 11th, 2019

In the latest version of Ubuntu (19.04), ifconfig is not installed by default anymore.

If you need to find your wifi mac address while you have no network connection, you cannot install ifconfig so you need a different way to find your wifi mac address:

Do `cat /sys/class/net/<network_connection_name>/address` to display the wifi’s mac address.

On a default installation, <network_connection_name> is most likely wlo1. If it’s not, use tab completion, in all likeliness there are only three files in the net folder: the wired network adapter, the wifi adapter and the loopback address.

IT Security for home users – keep your applications up to date

Friday, March 1st, 2019

Windows

ninite

My personal suggestion is ninite, to be found at https://ninite.com/

Select the applications you want to use, download the installer and run it only a daily basis – it will keep you up to date and safe(r)

MacOS

AppStore

Love it or hate it, but minor applications can easily be installed via the AppStore e.g. Line or Slack

Advantage: You will get an update notification from the AppStore if an update is available

Brew

Follow the instructions on the brew HP: https://brew.sh/

Once this is done, you can install, update or uninstall applications from the command line

Installs

brew install wget

brew cask install macvim

brew cask install gimp

brew cask install libreoffice

brew cask install quodlibet

brew cask install virtualbox

brew cask install chromium

brew cask install projectlibre

brew cask install vlc

brew cask install skype

brew cask install minikube

brew cask install firefox

brew cask install keepassx

brew cask install box-sync

Uninstall

brew cask uninstall <cask_name>

Upgrade

brew update && brew outdated && brew upgrade && brew cleanup

IT Security for home users – upgrade your OS

Thursday, February 28th, 2019

The mainstream operation systems (including mobile OSes) have an upgrade function (in case of a mobile OS, whether your carrier releases updates is a different story….)

Use that function and install those updates!

macOS: Go to the Apple icon, select “About This Mac” and click on “Software Update…” Most of the updates require a reboot, even on MacOS.

Windows: From the “Windows Settings”, go to “Update & Security”. Check for updates, install what’s available and reboot.

Ubuntu: Run ‘sudo apt-get update && apt-get dist-upgrade’
(if you feel like protesting because <your valid reason here>, then you already know what you’re doing and you shouldn’t be reading this anyway (unless you want to fact-check my ramblings))
Other Linux versions use different commands, if you’re unsure, google for the appropriate command on your platform.

IT security for home users – a simple guide (overview)

Tuesday, February 26th, 2019

I have been thinking about writing about this for a while… there is much information on staying secure out there and everything, I repeat, everything can already be read and practiced, even as a home user.

But maybe it bears repeating… so why not summarize some good practices here and maybe add my two cents.

Trying to stay secure as a home user usually comes down to just a couple of things:

  1. Upgrade your OS
  2. Disable what you don’t need
  3. Upgrade your application
  4. Change default passwords
  5. Upgrade anything else

Did I mention “upgrade <your stuff here>” already? You should do that.

If you fear breaking stuff by upgrading, then don’t upgrade *right away* – in IT, we say “avoid x.0 releases”. This applies to both OS and applications.
Wait for a x.1 or better x.2 release and install that one. Many vendors work hard to release good products but just as many release under time pressure and cut corners to make it in time, to save costs etc. It happens.

Keep coming back to read the details.

anti-mining malware measures

Tuesday, February 5th, 2019

A recent article on heise (https://www.heise.de/ratgeber/Mining-Parasiten-erkennen-und-loswerden-4198965.html) outlined how one can investigate a possible infection of a mining trojan on one’s computer. Typical symptoms of such an infection include a high CPU usage (usually resulting in the fan spinning despite running no high-load applications).

The general way to go on about this is to identify the process causing the high load and terminating it. On Windows, the OS-included application to use for that is TaskManager, on MacOS it’s Activity Monitor. On Windows platform, one other freely available tool is ProcessExplorer by Sysinternals.
Using those tools, it’s easy to list the running processes, sort them by CPU percentage and terminating them.

There is a serious limiting factor to this solution, however.

As malware creators are also getting more proficient, some of them include checks in the malware binaries which terminate the mining processes as soon as tools resp. their process names such as Taskmgr.exe, Activity Monitor or procexp64.exe are detected running.

The article therefor recommends to rename the binaries and running them again. This way, the malware will not suspend its activity and can easily be identified and subsequently be terminated.

On earlier Windows platforms, copying taskmgr.exe and renaming it was straightforward. On Windows 10 however, a renamed Task Manager binary does not display any data – I’m still trying to figure this one out.

Renaming procexp64.exe however is straight-forward. Extract the binary from the downloaded zip file, rename it and off you go.

On macOS Mojave (10.14.x) and High Sierra (10.13.x), Activiy Monitor can be renamed as follows:
Open the Utilities folder
Copy and paste Activity Monitor (provide an administrator password if asked)
From the context menu of the copied item, select “Rename”
From the context menu of the renamed item, select “Show Package Contents”
In the subfolder MacOS, rename Activity Monitor
In the Contents folder, open Info.plist
Change the following strings to the name you chose: Executable file, Bundle name, Bundle display name

Run the renamed Activity Monitor binary by running the Unix executable in the folder MacOS

phone number? f*** u, twitter

Thursday, December 20th, 2018

For some reasons I spent a lot of time recently thinking I would like to try twitter. Probably it’s because there is twitter desktop client availabe in linux distributions… corebird

So I signed up on twitter using my email address. After a couple of days, the account was suspended for “breaking the rules” – which is pretty amazing given that I’ve never twitted anything so far.

the only way to un-suspend the account? (re-animate?) provide a (mobile) phone number. well, fark you… not going to happen.

I’ve tried to find alternatives… there seem to be some but I’m not going to spend time creating fake phone numbers just to try to stay ahead in a game of cats and mice for a short while as twitter seems to be really strict about it and blocking phone number blocks and not allowing this and that.

update: fixed two typos