502 Bad Gateway is one of the most infamous errors on the backend, it usually means “hey something wrong with your backend server” but it doesn’t really give enough information. 

In this video, 

I’ll go through details on why proxies and gateways like NGINX and HAProxy should consider throwing more fine detailed HTTP error codes.   502 Bad Gateway The server was acting as a gateway or proxy and received an invalid response from the upstream server.  

0:00 intro  

3:45 What Causes a 502 Bad Gateway?

8:00 Cloudflare HTTP error codes 

13:00 Security Implications

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In this episode I’ll talk about how VPN works, networking, IPSec and will also discuss the benefits of VPN and what happens when a VPN is hacked?

  * Intro 0:00

  * How Networking Works? 2:20

  * How VPN Works? 10:00

  * VPN Benefits 17:50

 * What happens when VPN is hacked 20:20

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There is an ongoing situation with the Linux kernel community and the University of Minnesota Department of Computer Science & Engineering. We discuss this in this episode and I give my opinion

Let us discuss the complexity behind this trojan hack, the multi-layer approach of hiding the RAT (remote access trojan) is absolutely genius.

https://en.wikipedia.org/wiki/HTML_Application https://en.wikipedia.org/wiki/Portable_Network_Graphics https://blog.malwarebytes.com/malwarebytes-news/2021/04/lazarus-apt-conceals-malicious-code-within-bmp-file-to-drop-its-rat/

Leaky abstractions occur when the consumer of the abstraction started asking questions about certain behavior which ends up with the need to understand the details behind the abstraction. Joel Spolsky coined this term and in this video I’d like to discuss this concept and provide few examples of my own experience towards leaky abstractions. Let us get on with the show.

6:00 Postgres Dead Tuples

7:25 MySQL Clustering

9:23 Axios HTTP Library

11:30 ORMs (N+1)

13:30 Beyond Abstractions

15:30 TCP

19:30 HTTP/2

27:00 Microservices

28:40 Index Only Scans Postgres

33:35 git

34:50 Summary

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Two weeks ago the PHP source code git server got hacked and two malicious commits were made to the source code. Since then the PHP maintainers identified the source of the hack, let us discuss

Light episode today let's have some fun with Q&A, I collected some questions on Twitter and YouTube community and I'm going to attempt to answer them here.

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In this episode, we will discuss NULLs in database systems. I’ll go through the following:

What is Null?

NULLs persistence

When NULLs are naughty

When NULLs are useful

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