What is a DDOS? Explaining it to your grandmother

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What is a DDOS? Explaining it to your grandmother

October 24th, 2016 by Jeanne Boyarsky

After Friday’s internet attack, I had to explain what a DDOS (Distributed Denial of Service) attack was to my mother. She’s not so good with computers which is why her computer is a Chromebook. Here’s what I came up with:

Imagine I ring your doorbell and then run around the corner. You answer the door, but nobody is there. I do this every hour for six hours. Annoying right? Now imagine I recruit 100 people to do the same thing. Now your doorbell is ringing every 30 seconds. Eek! That’s a DDOS.

What do you think? Good analogy?

FIRST robotics 2017 background check and social security number

October 9th, 2016 by Jeanne Boyarsky

This year, when you register to volunteer with FIRST Robotics in VIMS, you get prompted to register in Verified Volunteers so they can do a background check. In particular to determine you don’t have a criminal history and aren’t a sex offender.  For the most part, this is straightforward. You give some minimal information about yourself. And FIRST pays the cost of the background check.US FIRST - V2


Wait? They want my Social Security Number?

The only thing in the background check that could be considered sensitive is your Social Security Number. FIRST doesn’t get this information if you choose to provide it. But Verified Volunteers does.

I have a “real” background check for my job. So I don’t have a problem with the concept of a background check. I’m not a big fan of providing unnecessary information though. Especially given the number of data breaches lately. Luckily, FIRST says you don’t have to provide it in their volunteer screening guide:



Wait, does this work?

Yes. I chose to check the “No SSN” button. I was screened within 48 hours.

How much does it cost?

As a volunteer, it costs nothing. It costs FIRST money though. $8 for the national screening. And since I am in New York State, they also paid $65 for a state one. This adds up fast. Which means FIRST is spending many thousands of dollars on background checks.

There is a thread on chief delphi about this. It’s hard to find the relevant info without reading the whole thread so putting up this blog post for easy reference.

getting an old file in git from a directory than no longer exists

September 24th, 2016 by Jeanne Boyarsky

Some time ago, I had deleted a file in git along with renaming the directory it was in. I had wanted to rename the file rather than delete it. So now I needed it back. This took a few steps so I decided to blog what I did.

Step 1 – find the command to get the commit number for my deletion

I had no idea how to do this so I googled it. A comment on this post was really helpful. On OSX, I ran:

git log --diff-filter=D --summary | sed -n -e '/^commit/h' -e '\:/:{' -e G -e 's/\ncommit \(.*\)/ \1/gp' -e }

While I understand this, I never would have thought to write it.

This gave me a list of all my commits. Then I added | grep myFileName to it and I got the commit where this file was deleted.

Step 2 – Look at commit details

Next I did a git show to see whether it was me or my teammate that

git show myCommitId

It was me. I didn’t know that at the start. Oops!

Step 3 – Retrieve the file

It is possible to do a git checkout of just one file. However the folder structure doesn’t exist anymore in the latest, so this would be a pain. I decided to just get the file from the github UI. I ran the following (with real values for myRepo and myCommitId).


Then I viewed and downloaded it. Yay. My image file is back.

Step 4 – Commit again

I renamed the file again and added/committed normally.

Done! It’s now like this mistake never happened. Except in git history!