Press "Enter" to skip to content

Category: Learnings

How to get rid of stickers on your Macbook


MacBook Pro with open source project stickersIf you are roaming the open source world, chances are you’ve either come across people who have tons of stickers of various projects on their laptops or you yourself made sure it has ample sticker coverage.
But what if you want to sell your laptop, or have to return it to your employer in a clean state? Get ready to invest some elbow grease.
I simply decided to go more with the clean and simple look on my MacBook Pro and so the
stickers had to go. I thought I’d share a very simple way as I found a wide range of solutions varying in complexity and chances of success.
This is only aimed at MacBooks as other laptops (like my beloved Thinkpads) have different surface materials which may or may not react different.
First you will need some paint thinner:
Can of paint thinner used for cleaning
I started by simply pulling off everything I could with my fingers and finger nails. Some stickers are easy, others not so much. Get off as much as possible.
Next get some paint thinner on a paper kitchen towel and begin to rub it first into the remains of the sticker and then in circular motions with some pressure until the glue part dissolves. Keep going and make sure every part of the sticker comes off. Wipe off multiple times to not just spread the remains all over the lid.
Once you got it all off use a clean paper towel with some paint thinner and give it a final wipe. Then use yet another clean and damp paper towel and wipe off the remaining paint thinner (it smells terrible).
The end result should look like this:
Cleaned up MacBook Pro with old stickers in the back
Make sure you do this in a well ventilated room or ideally outside. This stuff really can cause some nasty headaches.

Deallocating multiple VMs with azure-cli & bash

The great thing about Azure (and to that extent Azure Stack) is that you can quickly spin up and down test environments. If you’re like me, you prefer a command line over any browser interface any day of the week for repeatable tasks.
In the Azure world, the great azure-cli command line tool comes to the rescue. The great thing about it is that it is a) open source, and b) cross platform. So working with resources in Azure from my Linux workstation is no problem. Until I ran into one.
For testing out some network configurations, I spun up a bunch of VMs in Azure. Once I was done, I wanted to deallocate them to not have them consume resources, and thus cost money. That’s after all the great thing about a cloud.
All my VMs were in their own resource group to have a dedicated network for them and since it’s a test lab, easy to manage without interferring with other resources. The azure-cli provides the functionality on a per VM basis to deallocate a VM from the shell. That is all good for one, but not for multiples. Let’s take a look:

mschulz@eowyn:~$ azure vm list -g db2lab
 info:    Executing command vm list
 + Getting virtual machines
 data:    ResourceGroupName  Name       ProvisioningState  PowerState      Location  Size
 data:    -----------------  ---------  -----------------  --------------  --------  ----
 data:    db2lab             db2-node1  Succeeded          VM running       westus    Standard_A2
 data:    db2lab             db2-node2  Succeeded          VM running       westus    Standard_A2
 info:    vm list command OK
 This is the environment for the simple test. Two VMs (more to be added) to form a cluster in resource group db2lab.

The azure-cli tool provides us the name of the resource group, as well as the VM names.
From here we can do a simple one liner to get the respective VM names we want to target and write
them into an array for later processing:

mschulz@eowyn:~$ vmname=($(azure vm list |grep -i db2lab | awk '{print $3}'))
 mschulz@eowyn:~$ echo ${vmname[@]}
 db2-node1 db2-node2
 Now that we have those names in the array, we can then proceed to process them in a simple loop that
 will take the action on the VMs we want.
for i in "${vmname[@]}"
 do :
 azure vm deallocate –g db2lab -n $i

The above example reads the values from the array, passes them to the azure-cli and deallocates the VMs. In order to do the revers, we could simply replace deallocate with start.
Since this would be a bit cumbersome to do every time we need this operation, let’s pull all this together in a handy shell script:

startvms() {
         vmname=($(azure vm list |grep -i $rgroup | awk '{print $3}'))
         for i in "${vmname[@]}"
 do :
 azure vm start -g $rgroup -n $i
stopvms() {
         vmname=($(azure vm list |grep -i $rgroup | awk '{print $3}'))
         for i in "${vmname[@]}"
 do :
 azure vm stop -g $rgroup -n $i
deallocvms() {
         vmname=($(azure vm list |grep -i $rgroup | awk '{print $3}'))
         for i in "${vmname[@]}"
 do :
 azure vm deallocate -g $rgroup -n $i
case $2 in
 start)  startvms ;;
 stop)   stopvms ;;
 deallocate)     deallocvms ;;
 *)      echo "usage: $0 "resource group" start|stop|deallocate" >&2
 exit 1

Using this script, we can now on the command line specifiy the resource group in question, plus
define the action we want to be taken (start, stop, or deallocate).

The azure-cli tool is a fantastic resource in the tool belt of the Azure admin to perform many tasks from the command line of either Linux, WIndows, or Mac OS X. Look Ma’, no GUI.


Elecraft K1 – Day 3

Progress is being made … but organization comes first.

K1 day3 organized

I can just highly recommend sorting parts first. Especially when you have parts where the numbers are hard
to read because of their size. This makes the build process go much smoother.

K1 day3 mainboard

Managed to get some parts mounted on day 3 of the build on the RF board. This will be a longer process. This
is fine though, as building this little radio is half the fun. More to come.